Shareholder Report, Holdings (Details)
|
Apr. 30, 2026 |
| C000229439 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229439 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229439 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229439 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229439 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229439 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229439 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229439 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229439 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229439 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229439 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229439 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229439 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229439 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229439 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229439 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229439 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229439 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229439 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229439 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229439 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229439 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229439 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229439 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229439 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229439 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229439 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229439 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229439 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229442 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229442 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229442 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229442 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229442 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229442 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229442 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229442 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229442 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229442 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229442 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229442 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229442 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229442 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229442 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229442 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229442 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229442 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229442 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229442 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229442 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229442 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229442 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229442 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229442 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229442 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229442 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229442 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229442 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229441 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229441 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229441 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229441 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229441 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229441 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229441 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229441 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229441 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229441 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229441 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229441 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229441 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229441 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229441 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229441 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229441 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229441 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229441 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229441 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229441 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229441 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229441 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229441 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229441 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229441 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229441 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229441 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229441 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229440 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229440 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229440 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229440 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229440 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229440 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229440 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229440 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229440 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229440 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229440 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229440 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229440 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229440 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229440 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229440 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229440 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229440 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229440 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229440 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229440 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229440 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229440 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229440 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229440 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229440 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229440 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229440 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229440 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229443 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229443 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229443 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229443 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229443 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229443 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229443 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229443 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229443 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229443 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229443 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229443 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229443 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229443 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229443 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229443 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229443 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229443 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229443 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229443 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229443 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229443 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229443 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229443 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229443 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229443 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229443 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229443 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229443 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229438 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229438 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229438 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229438 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229438 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229438 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229438 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229438 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229438 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229438 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229438 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229438 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229438 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229438 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229438 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229438 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229438 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229438 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229438 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229438 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229438 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229438 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229438 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229438 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229438 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229438 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229438 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229438 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229438 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229437 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229437 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229437 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229437 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229437 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229437 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229437 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229437 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229437 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229437 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229437 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229437 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229437 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229437 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229437 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229437 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229437 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229437 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229437 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229437 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229437 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229437 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229437 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229437 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229437 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229437 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229437 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229437 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229437 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000229436 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229436 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229436 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229436 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000229436 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000229436 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000229436 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229436 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000229436 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229436 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000229436 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229436 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000229436 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000229436 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000229436 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229436 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229436 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229436 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000229436 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000229436 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000229436 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000229436 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000229436 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000229436 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229436 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000229436 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000229436 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000229436 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000229436 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000236387 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236387 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236387 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236387 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236387 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236387 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236387 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236387 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236387 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236390 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236390 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236390 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236390 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236390 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236390 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236390 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236390 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236390 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236393 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236393 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236393 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236393 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236393 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236393 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236393 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236393 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236393 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236388 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236388 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236388 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236388 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236388 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236388 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236388 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236388 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236388 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236386 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236386 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236386 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236386 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236386 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236386 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236386 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236386 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236386 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236389 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236389 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236389 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236389 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236389 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236389 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236389 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236389 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236389 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236392 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236392 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236392 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236392 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236392 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236392 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236392 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236392 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236392 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000236391 [Member] | Fitch, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000236391 [Member] | Fitch, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
14.30%
|
| C000236391 [Member] | Fitch, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
17.10%
|
| C000236391 [Member] | Money Market Funds Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236391 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.80%
|
| C000236391 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
22.70%
|
| C000236391 [Member] | Fixed Income Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
95.40%
|
| C000236391 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000236391 [Member] | Federal Agencies [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.50%
|
| C000173915 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173915 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173915 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173915 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173915 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173915 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173915 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173915 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173915 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173915 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173915 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173915 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173915 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173915 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173915 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173915 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173915 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173915 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173915 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173915 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173915 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173915 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173915 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173915 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173915 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173915 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173915 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173915 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173915 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173916 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173916 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173916 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173916 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173916 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173916 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173916 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173916 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173916 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173916 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173916 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173916 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173916 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173916 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173916 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173916 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173916 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173916 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173916 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173916 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173916 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173916 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173916 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173916 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173916 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173916 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173916 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173916 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173916 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173917 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173917 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173917 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173917 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173917 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173917 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173917 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173917 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173917 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173917 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173917 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173917 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173917 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173917 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173917 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173917 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173917 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173917 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173917 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173917 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173917 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173917 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173917 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173917 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173917 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173917 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173917 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173917 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173917 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173918 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173918 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173918 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173918 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173918 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173918 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173918 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173918 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173918 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173918 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173918 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173918 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173918 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173918 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173918 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173918 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173918 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173918 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173918 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173918 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173918 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173918 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173918 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173918 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173918 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173918 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173918 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173918 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173918 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119453 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119453 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119453 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119453 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119453 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119453 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119453 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119453 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119453 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119453 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119453 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119453 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119453 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119453 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119453 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119453 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119453 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119453 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119453 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119453 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119453 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119453 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119453 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119453 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119453 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119453 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119453 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119453 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119453 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119454 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119454 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119454 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119454 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119454 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119454 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119454 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119454 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119454 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119454 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119454 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119454 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119454 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119454 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119454 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119454 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119454 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119454 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119454 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119454 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119454 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119454 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119454 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119454 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119454 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119454 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119454 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119454 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119454 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173233 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173233 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173233 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173233 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173233 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173233 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173233 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173233 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000173233 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173233 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173233 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173233 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173233 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173233 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173233 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173233 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173233 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000173233 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173233 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000173233 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173233 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000173233 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000173233 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173233 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173233 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173233 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000173233 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173233 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000173233 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173923 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173923 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173923 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173923 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173923 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173923 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173923 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173923 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173923 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173923 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173923 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173923 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173923 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173923 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173923 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173923 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173923 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173923 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173923 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173923 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173923 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173923 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173923 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173923 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173923 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173923 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173923 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173923 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173923 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173922 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173922 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173922 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173922 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173922 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173922 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173922 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173922 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173922 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173922 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173922 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173922 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173922 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173922 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173922 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173922 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173922 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173922 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173922 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173922 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173922 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173922 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173922 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173922 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173922 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173922 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173922 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173922 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173922 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173919 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173919 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173919 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173919 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173919 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173919 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173919 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173919 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173919 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173919 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173919 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173919 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173919 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173919 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173919 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173919 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173919 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173919 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173919 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173919 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173919 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173919 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173919 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173919 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173919 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173919 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173919 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173919 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173919 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173920 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173920 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173920 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173920 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173920 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173920 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173920 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173920 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173920 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173920 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173920 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173920 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173920 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173920 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173920 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173920 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173920 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173920 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173920 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173920 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173920 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173920 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173920 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173920 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173920 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173920 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173920 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173920 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173920 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173921 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173921 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173921 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173921 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173921 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173921 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173921 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173921 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173921 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173921 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173921 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173921 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173921 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173921 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173921 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173921 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173921 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173921 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173921 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173921 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173921 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.10%
|
| C000173921 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173921 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173921 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173921 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173921 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173921 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173921 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.90%
|
| C000173921 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173232 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000173232 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173232 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173232 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173232 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000173232 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000173232 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000173232 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000173232 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000173232 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173232 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173232 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173232 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173232 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000173232 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000173232 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173232 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173232 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000173232 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000173232 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000173232 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000173232 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000173232 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173232 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000173232 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000173232 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000173232 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000173232 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000173232 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173232 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000173232 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000173232 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000173232 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119446 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119446 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119446 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119446 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119446 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119446 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119446 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119446 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119446 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119446 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119446 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119446 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119446 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119446 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119446 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119446 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119446 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119446 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119446 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119446 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119446 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119446 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119446 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119446 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119446 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119446 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119446 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119446 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119446 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119446 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119446 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119446 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119446 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119442 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119442 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119442 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119442 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119442 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119442 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119442 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119442 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119442 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119442 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119442 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119442 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119442 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119442 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119442 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119442 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119442 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119442 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119442 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119442 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119442 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119442 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119442 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119442 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119442 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119442 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119442 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119442 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119442 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119442 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119442 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119442 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119442 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119443 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119443 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119443 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119443 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119443 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119443 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119443 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119443 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119443 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119443 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119443 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119443 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119443 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119443 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119443 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119443 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119443 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119443 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119443 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119443 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119443 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119443 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119443 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119443 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119443 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119443 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119443 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119443 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119443 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119443 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119443 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119443 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119443 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119444 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119444 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119444 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119444 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119444 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119444 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119444 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119444 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119444 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119444 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119444 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119444 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119444 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119444 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119444 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119444 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119444 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119444 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119444 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119444 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119444 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119444 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119444 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119444 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119444 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119444 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119444 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119444 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119444 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119444 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119444 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119444 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119444 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119445 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119445 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119445 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119445 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119445 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119445 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119445 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119445 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119445 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119445 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119445 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119445 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119445 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119445 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119445 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119445 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119445 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119445 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119445 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119445 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119445 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119445 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119445 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119445 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119445 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119445 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119445 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119445 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119445 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119445 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119445 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119445 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119445 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119447 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119447 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119447 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119447 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119447 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119447 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119447 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119447 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119447 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119447 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119447 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119447 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119447 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119447 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119447 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119447 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119447 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119447 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119447 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119447 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119447 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119447 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119447 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119447 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119447 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119447 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119447 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119447 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119447 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119448 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119448 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119448 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119448 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119448 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119448 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119448 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119448 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119448 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119448 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119448 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119448 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119448 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119448 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119448 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119448 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119448 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119448 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119448 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119448 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119448 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119448 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119448 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119448 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119448 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119448 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119448 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119448 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119448 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119449 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119449 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119449 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119449 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119449 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119449 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119449 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119449 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119449 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119449 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119449 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119449 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119449 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119449 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119449 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119449 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119449 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119449 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119449 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119449 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119449 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119449 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119449 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119449 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119449 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119449 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119449 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119449 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119449 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119450 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119450 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119450 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119450 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119450 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119450 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119450 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119450 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119450 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119450 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119450 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119450 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119450 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119450 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119450 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119450 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119450 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119450 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119450 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119450 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119450 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119450 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119450 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119450 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119450 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119450 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119450 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119450 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119450 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119451 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119451 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119451 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119451 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119451 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119451 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119451 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119451 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119451 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119451 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119451 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119451 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119451 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119451 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119451 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119451 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119451 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119451 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119451 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119451 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119451 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119451 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119451 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119451 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119451 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119451 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119451 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119451 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119451 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000119452 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119452 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119452 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119452 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000119452 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000119452 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119452 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119452 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.10%
|
| C000119452 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119452 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119452 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119452 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119452 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119452 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119452 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119452 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000119452 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119452 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000119452 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000119452 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000119452 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.20%
|
| C000119452 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000119452 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119452 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119452 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119452 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000119452 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119452 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.80%
|
| C000119452 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
28.30%
|
| C000173229 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173229 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000173229 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173229 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173229 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173229 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173229 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173229 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173229 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000173229 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173229 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000173229 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000173229 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000173229 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000173229 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173229 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173229 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000173229 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000173229 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173229 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000173229 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000173229 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000173229 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000173229 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173229 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173229 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000173229 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000173229 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000173229 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173229 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173229 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000173229 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000173229 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000119423 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119423 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119423 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119423 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119423 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119423 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119423 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119423 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119423 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119423 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119423 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119423 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119423 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119423 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119423 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119423 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119423 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119423 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119423 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119423 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119423 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119423 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119423 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119423 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119423 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119423 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119423 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119423 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119423 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119423 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119423 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119423 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119430 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119430 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119430 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119430 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119430 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119430 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119430 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119430 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119430 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119430 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119430 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119430 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119430 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119430 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119430 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119430 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119430 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119430 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119430 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119430 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119430 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119430 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119430 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119430 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119430 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119430 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119430 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119430 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119430 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119430 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119430 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119430 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119424 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119424 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119424 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119424 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119424 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119424 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119424 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119424 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119424 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119424 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119424 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119424 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119424 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119424 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119424 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119424 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119424 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119424 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119424 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119424 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119424 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119424 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119424 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119424 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119424 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119424 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119424 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119424 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119424 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119424 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119424 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119424 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119425 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119425 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119425 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119425 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119425 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119425 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119425 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119425 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119425 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119425 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119425 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119425 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119425 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119425 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119425 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119425 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119425 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119425 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119425 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119425 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119425 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119425 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119425 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119425 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119425 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119425 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119425 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119425 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119425 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119425 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119425 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119425 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119426 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119426 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119426 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119426 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119426 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119426 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119426 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119426 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119426 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119426 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119426 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119426 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119426 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119426 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119426 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119426 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119426 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119426 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119426 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119426 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119426 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119426 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119426 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119426 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119426 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119426 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119426 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119426 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119426 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119426 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119426 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119426 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119427 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119427 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119427 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119427 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119427 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119427 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119427 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119427 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119427 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119427 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119427 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119427 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119427 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119427 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119427 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119427 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119427 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119427 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119427 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119427 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119427 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119427 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119427 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119427 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119427 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119427 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119427 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119427 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119427 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119427 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119427 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119427 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119428 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119428 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119428 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119428 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119428 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119428 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119428 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119428 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119428 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119428 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119428 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119428 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119428 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119428 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119428 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119428 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119428 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119428 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119428 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119428 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119428 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119428 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119428 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119428 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119428 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119428 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119428 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119428 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119428 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119428 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119428 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119428 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000119429 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119429 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119429 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119429 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119429 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000119429 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119429 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000119429 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119429 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119429 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119429 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119429 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119429 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000119429 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119429 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119429 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119429 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000119429 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119429 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119429 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119429 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119429 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000119429 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119429 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000119429 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119429 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000119429 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000119429 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119429 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000119429 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119429 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000119429 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173230 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173230 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173230 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173230 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000173230 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173230 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173230 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000173230 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173230 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173230 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173230 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000173230 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000173230 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173230 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173230 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173230 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173230 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000173230 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000173230 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173230 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173230 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000173230 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173230 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173230 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000173230 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173230 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173230 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
20.00%
|
| C000173230 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173230 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.90%
|
| C000173230 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173230 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.60%
|
| C000173230 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092196 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092196 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092196 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092196 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092196 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092196 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092196 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092196 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092196 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092196 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092196 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092196 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092196 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092196 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092196 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092196 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092196 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092196 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092196 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092196 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092196 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092196 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092196 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092196 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092196 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092196 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092196 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092196 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092196 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092196 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092196 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092196 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092196 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092197 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092197 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092197 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092197 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092197 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092197 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092197 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092197 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092197 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092197 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092197 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092197 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092197 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092197 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092197 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092197 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092197 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092197 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092197 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092197 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092197 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092197 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092197 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092197 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092197 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092197 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092197 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092197 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092197 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092197 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092197 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092197 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092197 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092198 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092198 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092198 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092198 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092198 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092198 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092198 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092198 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092198 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092198 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092198 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092198 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092198 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092198 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092198 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092198 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092198 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092198 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092198 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092198 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092198 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092198 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092198 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092198 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092198 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092198 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092198 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092198 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092198 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092198 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092198 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092198 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092198 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092199 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092199 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092199 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092199 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092199 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092199 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092199 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092199 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092199 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092199 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092199 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092199 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092199 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092199 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092199 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092199 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092199 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092199 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092199 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092199 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092199 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092199 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092199 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092199 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092199 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092199 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092199 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092199 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092199 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092199 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092199 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092199 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092199 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092200 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092200 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092200 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092200 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092200 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092200 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092200 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092200 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092200 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092200 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092200 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092200 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092200 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092200 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092200 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092200 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092200 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092200 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092200 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092200 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092200 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092200 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092200 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092200 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092200 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092200 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092200 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092200 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092200 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092200 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092200 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092200 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092200 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092201 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092201 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092201 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092201 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092201 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092201 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092201 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092201 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092201 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092201 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092201 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092201 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092201 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092201 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092201 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092201 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092201 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092201 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092201 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092201 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092201 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092201 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092201 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092201 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092201 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092201 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092201 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092201 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092201 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092201 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092201 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092201 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092201 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092202 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092202 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092202 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092202 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092202 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092202 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092202 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092202 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092202 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092202 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092202 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092202 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092202 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092202 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092202 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092202 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092202 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092202 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092202 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092202 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092202 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092202 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092202 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092202 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092202 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092202 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092202 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092202 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092202 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092202 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092202 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092202 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092202 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000092203 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092203 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092203 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092203 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000092203 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092203 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000092203 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000092203 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000092203 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092203 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092203 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.40%
|
| C000092203 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.30%
|
| C000092203 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000092203 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000092203 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000092203 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092203 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.30%
|
| C000092203 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092203 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000092203 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.50%
|
| C000092203 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000092203 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
11.00%
|
| C000092203 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.20%
|
| C000092203 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092203 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092203 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.20%
|
| C000092203 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092203 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.10%
|
| C000092203 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000092203 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000092203 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000092203 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
55.70%
|
| C000092203 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
27.90%
|
| C000119437 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119437 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119437 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119437 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119437 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119437 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119437 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119437 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119437 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119437 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119437 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119437 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119437 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119437 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119437 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119437 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119437 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119437 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119437 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119437 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119437 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119437 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119437 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119437 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119437 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119437 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119437 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119437 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119437 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119437 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119437 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119437 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119437 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119438 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119438 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119438 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119438 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119438 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119438 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119438 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119438 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119438 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119438 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119438 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119438 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119438 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119438 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119438 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119438 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119438 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119438 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119438 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119438 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119438 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119438 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119438 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119438 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119438 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119438 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119438 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119438 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119438 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119438 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119438 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119438 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119438 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000173231 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000173231 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000173231 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000173231 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000173231 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173231 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000173231 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173231 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000173231 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000173231 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173231 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000173231 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000173231 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000173231 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000173231 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000173231 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173231 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000173231 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000173231 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000173231 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173231 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173231 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000173231 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000173231 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000173231 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000173231 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000173231 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000173231 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173231 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173231 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000173231 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000173231 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000173231 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119439 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119439 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119439 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119439 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119439 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119439 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119439 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119439 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119439 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119439 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119439 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119439 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119439 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119439 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119439 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119439 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119439 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119439 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119439 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119439 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119439 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119439 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119439 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119439 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119439 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119439 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119439 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119439 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119439 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119439 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119439 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119439 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119439 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119440 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119440 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119440 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119440 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119440 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119440 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119440 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119440 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119440 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119440 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119440 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119440 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119440 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119440 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119440 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119440 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119440 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119440 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119440 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119440 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119440 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119440 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119440 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119440 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119440 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119440 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119440 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119440 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119440 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119440 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119440 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119440 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119440 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119441 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000119441 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119441 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119441 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000119441 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119441 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000119441 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119441 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.50%
|
| C000119441 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000119441 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119441 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.20%
|
| C000119441 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119441 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000119441 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000119441 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.80%
|
| C000119441 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119441 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119441 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119441 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.70%
|
| C000119441 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.30%
|
| C000119441 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119441 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119441 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119441 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119441 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119441 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119441 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.60%
|
| C000119441 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.10%
|
| C000119441 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119441 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
12.80%
|
| C000119441 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000119441 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
53.30%
|
| C000119441 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
24.00%
|
| C000119431 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119431 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119431 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119431 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119431 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119431 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119431 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119431 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119431 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119431 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119431 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119431 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119431 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119431 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119431 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119431 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119431 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119431 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119431 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119431 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119431 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119431 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119431 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119431 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119431 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119431 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119431 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119431 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119431 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119431 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119431 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119431 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119431 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119432 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119432 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119432 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119432 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119432 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119432 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119432 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119432 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119432 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119432 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119432 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119432 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119432 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119432 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119432 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119432 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119432 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119432 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119432 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119432 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119432 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119432 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119432 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119432 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119432 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119432 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119432 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119432 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119432 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119432 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119432 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119432 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119432 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119433 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119433 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119433 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119433 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119433 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119433 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119433 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119433 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119433 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119433 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119433 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119433 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119433 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119433 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119433 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119433 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119433 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119433 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119433 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119433 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119433 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119433 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119433 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119433 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119433 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119433 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119433 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119433 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119433 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119433 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119433 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119433 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119433 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119434 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119434 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119434 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119434 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119434 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119434 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119434 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119434 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119434 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119434 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119434 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119434 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119434 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119434 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119434 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119434 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119434 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119434 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119434 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119434 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119434 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119434 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119434 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119434 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119434 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119434 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119434 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119434 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119434 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119434 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119434 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119434 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119434 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119435 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119435 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119435 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119435 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119435 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119435 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119435 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119435 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119435 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119435 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119435 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119435 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119435 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119435 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119435 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119435 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119435 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119435 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119435 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119435 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119435 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119435 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119435 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119435 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119435 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119435 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119435 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119435 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119435 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119435 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119435 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119435 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119435 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000119436 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119436 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119436 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119436 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119436 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000119436 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000119436 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119436 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.80%
|
| C000119436 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119436 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000119436 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000119436 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.70%
|
| C000119436 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.60%
|
| C000119436 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000119436 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000119436 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119436 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.80%
|
| C000119436 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.20%
|
| C000119436 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.40%
|
| C000119436 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119436 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000119436 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.10%
|
| C000119436 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.70%
|
| C000119436 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000119436 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.10%
|
| C000119436 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000119436 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000119436 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119436 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000119436 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
41.10%
|
| C000119436 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.90%
|
| C000119436 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
39.00%
|
| C000119436 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
13.00%
|
| C000006829 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006829 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006829 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006829 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006829 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006829 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006829 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006829 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006829 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006829 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006829 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006829 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006829 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006829 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006829 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006829 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006829 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006829 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006829 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006829 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006829 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006829 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006829 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006829 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006829 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006829 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006829 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006829 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006829 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006829 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006829 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006829 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006829 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006829 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006830 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006830 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006830 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006830 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006830 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006830 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006830 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006830 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006830 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006830 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006830 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006830 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006830 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006830 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006830 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006830 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006830 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006830 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006830 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006830 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006830 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006830 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006830 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006830 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006830 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006830 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006830 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006830 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006830 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006830 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006830 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006830 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006830 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006830 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006831 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006831 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006831 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006831 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006831 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006831 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006831 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006831 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006831 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006831 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006831 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006831 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006831 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006831 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006831 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006831 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006831 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006831 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006831 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006831 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006831 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006831 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006831 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006831 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006831 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006831 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006831 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006831 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006831 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006831 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006831 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006831 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006831 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006831 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006832 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006832 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006832 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006832 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006832 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006832 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006832 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006832 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006832 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006832 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006832 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006832 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006832 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006832 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006832 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006832 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006832 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006832 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006832 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006832 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006832 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006832 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006832 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006832 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006832 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006832 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006832 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006832 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006832 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006832 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006832 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006832 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006832 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006832 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006833 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006833 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006833 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006833 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006833 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006833 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006833 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006833 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006833 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006833 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006833 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006833 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006833 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006833 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006833 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006833 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006833 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006833 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006833 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006833 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006833 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006833 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006833 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006833 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006833 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006833 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006833 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006833 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006833 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006833 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006833 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006833 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006833 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006833 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006835 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006835 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006835 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006835 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006835 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006835 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006835 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006835 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006835 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006835 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006835 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006835 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006835 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006835 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006835 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006835 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006835 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006835 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006835 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006835 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006835 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006835 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006835 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006835 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006835 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006835 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006835 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006835 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006835 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006835 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006835 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006835 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006835 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006835 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006836 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006836 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006836 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006836 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006836 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006836 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006836 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006836 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006836 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006836 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006836 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006836 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006836 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006836 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006836 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006836 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006836 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006836 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006836 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006836 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006836 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006836 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006836 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006836 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006836 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006836 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006836 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006836 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006836 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006836 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006836 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006836 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006836 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006836 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006837 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006837 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000006837 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006837 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006837 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006837 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000006837 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006837 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000006837 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006837 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006837 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000006837 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000006837 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000006837 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000006837 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000006837 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006837 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006837 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000006837 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000006837 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006837 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000006837 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000006837 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006837 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006837 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006837 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006837 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006837 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006837 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006837 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006837 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000006837 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000006837 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000006837 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006820 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006820 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006820 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006820 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006820 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006820 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006820 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006820 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006820 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006820 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006820 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006820 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006820 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006820 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006820 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006820 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006820 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006820 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006820 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006820 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006820 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006820 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006820 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006820 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006820 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006820 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006820 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006820 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006820 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006820 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006820 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006820 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006821 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006821 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006821 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006821 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006821 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006821 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006821 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006821 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006821 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006821 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006821 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006821 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006821 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006821 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006821 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006821 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006821 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006821 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006821 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006821 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006821 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006821 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006821 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006821 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006821 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006821 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006821 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006821 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006821 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006821 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006821 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006821 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006822 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006822 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006822 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006822 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006822 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006822 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006822 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006822 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006822 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006822 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006822 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006822 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006822 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006822 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006822 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006822 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006822 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006822 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006822 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006822 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006822 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006822 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006822 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006822 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006822 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006822 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006822 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006822 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006822 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006822 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006822 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006822 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006823 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006823 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006823 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006823 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006823 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006823 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006823 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006823 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006823 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006823 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006823 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006823 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006823 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006823 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006823 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006823 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006823 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006823 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006823 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006823 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006823 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006823 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006823 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006823 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006823 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006823 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006823 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006823 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006823 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006823 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006823 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006823 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006824 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006824 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006824 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006824 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006824 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006824 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006824 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006824 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006824 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006824 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006824 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006824 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006824 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006824 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006824 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006824 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006824 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006824 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006824 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006824 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006824 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006824 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006824 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006824 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006824 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006824 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006824 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006824 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006824 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006824 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006824 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006824 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006826 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006826 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006826 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006826 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006826 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006826 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006826 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006826 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006826 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006826 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006826 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006826 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006826 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006826 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006826 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006826 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006826 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006826 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006826 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006826 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006826 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006826 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006826 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006826 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006826 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006826 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006826 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006826 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006826 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006826 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006826 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006826 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006827 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006827 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006827 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006827 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006827 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006827 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006827 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006827 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006827 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006827 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006827 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006827 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006827 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006827 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006827 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006827 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006827 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006827 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006827 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006827 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006827 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006827 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006827 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006827 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006827 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006827 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006827 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006827 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006827 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006827 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006827 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006827 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000006828 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006828 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006828 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006828 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006828 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006828 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006828 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000006828 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000006828 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000006828 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000006828 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006828 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000006828 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006828 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006828 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006828 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006828 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006828 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000006828 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006828 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006828 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000006828 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006828 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006828 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000006828 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000006828 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000006828 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000006828 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000006828 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000006828 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006828 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000006828 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000173227 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000173227 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173227 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173227 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173227 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000173227 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173227 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173227 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.80%
|
| C000173227 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.00%
|
| C000173227 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000173227 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173227 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.60%
|
| C000173227 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173227 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173227 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173227 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173227 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000173227 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
15.30%
|
| C000173227 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173227 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173227 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.20%
|
| C000173227 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173227 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000173227 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
6.90%
|
| C000173227 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.90%
|
| C000173227 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.80%
|
| C000173227 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.90%
|
| C000173227 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173227 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
60.40%
|
| C000173227 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173227 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
26.30%
|
| C000173227 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.30%
|
| C000173228 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.00%
|
| C000173228 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.40%
|
| C000173228 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173228 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173228 [Member] | MFS International New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173228 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.50%
|
| C000173228 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173228 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.90%
|
| C000173228 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000173228 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173228 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.90%
|
| C000173228 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.70%
|
| C000173228 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.60%
|
| C000173228 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.90%
|
| C000173228 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.50%
|
| C000173228 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173228 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173228 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.00%
|
| C000173228 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.40%
|
| C000173228 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173228 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.40%
|
| C000173228 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
8.50%
|
| C000173228 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173228 [Member] | MFS Blended Research Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173228 [Member] | MFS Emerging Markets Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173228 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.90%
|
| C000173228 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000173228 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173228 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173228 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.90%
|
| C000173228 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
21.20%
|
| C000173228 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.90%
|
| C000173228 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
50.20%
|
| C000173228 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006793 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006793 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006793 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006793 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006793 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006793 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006793 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006793 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006793 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006793 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006793 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006793 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006793 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006793 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006793 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006793 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006793 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006793 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006793 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006793 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006793 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006793 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006793 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006793 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006793 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006793 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006793 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006793 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006793 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006793 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006793 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006793 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006794 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006794 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006794 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006794 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006794 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006794 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006794 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006794 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006794 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006794 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006794 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006794 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006794 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006794 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006794 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006794 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006794 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006794 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006794 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006794 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006794 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006794 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006794 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006794 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006794 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006794 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006794 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006794 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006794 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006794 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006794 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006794 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000173225 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000173225 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173225 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173225 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173225 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173225 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173225 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000173225 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173225 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173225 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173225 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173225 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000173225 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000173225 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000173225 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173225 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173225 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000173225 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000173225 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173225 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173225 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000173225 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000173225 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173225 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000173225 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173225 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000173225 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000173225 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000173225 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000173225 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000173225 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000173225 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006801 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006801 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006801 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006801 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006801 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006801 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006801 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006801 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006801 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006801 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006801 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006801 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006801 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006801 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006801 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006801 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006801 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006801 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006801 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006801 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006801 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006801 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006801 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006801 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006801 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006801 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006801 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006801 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006801 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006801 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006801 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006801 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006799 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006799 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006799 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006799 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006799 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006799 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006799 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006799 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006799 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006799 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006799 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006799 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006799 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006799 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006799 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006799 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006799 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006799 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006799 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006799 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006799 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006799 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006799 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006799 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006799 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006799 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006799 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006799 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006799 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006799 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006799 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006799 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006800 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006800 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006800 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006800 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006800 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006800 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006800 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006800 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006800 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006800 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006800 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006800 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006800 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006800 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006800 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006800 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006800 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006800 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006800 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006800 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006800 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006800 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006800 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006800 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006800 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006800 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006800 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006800 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006800 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006800 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006800 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006800 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006795 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006795 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006795 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006795 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006795 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006795 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006795 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006795 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006795 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006795 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006795 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006795 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006795 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006795 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006795 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006795 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006795 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006795 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006795 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006795 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006795 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006795 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006795 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006795 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006795 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006795 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006795 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006795 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006795 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006795 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006795 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006795 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006796 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006796 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006796 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006796 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006796 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006796 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006796 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006796 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006796 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006796 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006796 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006796 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006796 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006796 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006796 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006796 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006796 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006796 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006796 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006796 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006796 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006796 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006796 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006796 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006796 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006796 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006796 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006796 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006796 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006796 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006796 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006796 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|
| C000006797 [Member] | MFS Global Real Estate Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.10%
|
| C000006797 [Member] | MFS Mid Cap Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006797 [Member] | MFS Blended Research Core Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006797 [Member] | MFS Research Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006797 [Member] | MFS Research International Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006797 [Member] | MFS International Intrinsic Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006797 [Member] | MFS Blended Research Mid Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
3.10%
|
| C000006797 [Member] | MFS High Income Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006797 [Member] | MFS Blended Research Value Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006797 [Member] | MFS Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006797 [Member] | MFS Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006797 [Member] | MFS Blended Research Growth Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.70%
|
| C000006797 [Member] | MFS Commodity Strategy Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.00%
|
| C000006797 [Member] | MFS Mid Cap Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.50%
|
| C000006797 [Member] | MFS Institutional Money Market Portfolio [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006797 [Member] | MFS New Discovery Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006797 [Member] | MFS Inflation Adjusted Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
10.00%
|
| C000006797 [Member] | MFS Total Return Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006797 [Member] | MFS Blended Research Small Cap Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006797 [Member] | MFS International Growth Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006797 [Member] | MFS Blended Research International Equity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
2.80%
|
| C000006797 [Member] | MFS New Discovery Value Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
0.50%
|
| C000006797 [Member] | MFS Emerging Markets Debt Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006797 [Member] | MFS Global Opportunistic Bond Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
7.00%
|
| C000006797 [Member] | MFS Emerging Markets Debt Local Currency Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006797 [Member] | MFS Government Securities Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
9.90%
|
| C000006797 [Member] | MFS Limited Maturity Fund [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
19.80%
|
| C000006797 [Member] | Money Market Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
1.00%
|
| C000006797 [Member] | Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
70.50%
|
| C000006797 [Member] | Non Traditional Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
4.10%
|
| C000006797 [Member] | U S Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
18.90%
|
| C000006797 [Member] | International Equity Funds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Total Investments |
5.50%
|