Shareholder Report, Holdings (Details)
|
May 31, 2026 |
| C000106430 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000106430 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000106430 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000106430 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000106430 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000106430 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000106430 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000106430 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000106430 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000106430 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000106430 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000106430 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000106430 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000106430 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000106430 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000106430 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000106430 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000106430 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000106430 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000106430 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000106430 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000106430 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000106430 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000078713 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000078713 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000078713 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000078713 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000078713 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000078713 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000078713 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000078713 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000078713 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000078713 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000078713 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000078713 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000078713 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000078713 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000078713 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000078713 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000078713 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000078713 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000078713 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000078713 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000078713 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000078713 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000078713 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000078712 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000078712 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000078712 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000078712 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000078712 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000078712 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000078712 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000078712 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000078712 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000078712 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000078712 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000078712 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000078712 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000078712 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000078712 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000078712 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000078712 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000078712 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000078712 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000078712 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000078712 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000078712 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000078712 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000113489 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000113489 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000113489 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000113489 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000113489 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000113489 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000113489 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000113489 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000113489 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000113489 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000113489 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000113489 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000113489 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000113489 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000113489 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000113489 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000113489 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000113489 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000113489 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000113489 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000113489 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000113489 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000113489 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000001866 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000001866 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000001866 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001866 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000001866 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000001866 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000001866 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000001866 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000001866 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001866 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001866 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001866 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001866 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001866 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001866 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000001866 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000001866 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000001866 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000001866 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001866 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000001866 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001866 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001866 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000001865 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000001865 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000001865 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001865 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000001865 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000001865 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000001865 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000001865 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000001865 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001865 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001865 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001865 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001865 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001865 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001865 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000001865 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000001865 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000001865 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000001865 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001865 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000001865 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001865 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001865 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000001863 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.40%
|
| C000001863 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.50%
|
| C000001863 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001863 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.90%
|
| C000001863 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000001863 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.60%
|
| C000001863 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.20%
|
| C000001863 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000001863 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001863 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001863 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001863 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001863 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000001863 [Member] | Convertible bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000001863 [Member] | Preferred securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.30%
|
| C000001863 [Member] | Term loans [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.40%
|
| C000001863 [Member] | Foreign government obligations [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
24.80%
|
| C000001863 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000001863 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.60%
|
| C000001863 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.40%
|
| C000001863 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.00%
|
| C000001863 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000001863 [Member] | Corporate Bond Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
37.50%
|
| C000212730 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000212730 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.60%
|
| C000212730 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
77.30%
|
| C000212730 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
12.50%
|
| C000212730 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.60%
|
| C000212730 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.50%
|
| C000212730 [Member] | Energy Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
13.00%
|
| C000212730 [Member] | Financial Services Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
34.60%
|
| C000212730 [Member] | Healthcare Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.60%
|
| C000212730 [Member] | Real Estate Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.30%
|
| C000212730 [Member] | Communications Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.30%
|
| C000212730 [Member] | Consumer Discretionary Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.80%
|
| C000212730 [Member] | Consumer Staples Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.00%
|
| C000212730 [Member] | Industrial Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.30%
|
| C000212730 [Member] | Information Technology Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000212730 [Member] | Materials Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.20%
|
| C000212730 [Member] | Utilities Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
10.00%
|
| C000212730 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000212730 [Member] | Municipal Bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.10%
|
| C000212731 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.00%
|
| C000212731 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.00%
|
| C000212731 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
30.10%
|
| C000212731 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
58.60%
|
| C000212731 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.30%
|
| C000212731 [Member] | Energy Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.80%
|
| C000212731 [Member] | Financial Services Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
14.70%
|
| C000212731 [Member] | Healthcare Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.10%
|
| C000212731 [Member] | Real Estate Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.70%
|
| C000212731 [Member] | Communications Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
11.60%
|
| C000212731 [Member] | Consumer Discretionary Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
17.30%
|
| C000212731 [Member] | Consumer Staples Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.20%
|
| C000212731 [Member] | Industrial Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
7.30%
|
| C000212731 [Member] | Information Technology Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.70%
|
| C000212731 [Member] | Materials Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.70%
|
| C000212731 [Member] | Utilities Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
7.90%
|
| C000212731 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.00%
|
| C000212732 [Member] | Moody's, Aaa Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
49.70%
|
| C000212732 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000212732 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
15.00%
|
| C000212732 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
17.40%
|
| C000212732 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.50%
|
| C000212732 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
8.70%
|
| C000212732 [Member] | Mortgage Backed Security Issued by US Government Sponsored Enterprise Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.20%
|
| C000212732 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000212732 [Member] | Mortgage-Backed Securities, Issued by Private Enterprises [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
42.30%
|
| C000212732 [Member] | Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
5.20%
|
| C000212732 [Member] | Asset-Backed Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
51.00%
|
| C000238026 [Member] | CCC and below [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.80%
|
| C000238026 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.20%
|
| C000238026 [Member] | Standard & Poor's, B Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.30%
|
| C000238026 [Member] | Standard & Poor's, BB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
19.30%
|
| C000238026 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
17.40%
|
| C000238026 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.50%
|
| C000238026 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.20%
|
| C000238026 [Member] | Not rated [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
43.30%
|
| C000238026 [Member] | Healthcare Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
16.10%
|
| C000238026 [Member] | Pollution [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
0.10%
|
| C000238026 [Member] | Water and sewer [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.20%
|
| C000238026 [Member] | Housing [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.00%
|
| C000238026 [Member] | Tobacco [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.00%
|
| C000238026 [Member] | Airport [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.10%
|
| C000238026 [Member] | Development [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
19.20%
|
| C000238026 [Member] | Education [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
19.40%
|
| C000238026 [Member] | Transportation Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.60%
|
| C000238026 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
4.20%
|
| C000238026 [Member] | Other revenue [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
17.70%
|
| C000238026 [Member] | Revenue bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
89.40%
|
| C000238026 [Member] | General obligation bonds [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
6.40%
|
| C000247081 [Member] | Short term investments and other Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.70%
|
| C000247081 [Member] | Standard & Poor's, BBB Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
7.30%
|
| C000247081 [Member] | Standard & Poor's, A Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
7.00%
|
| C000247081 [Member] | Standard & Poor's, AA Rating [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.50%
|
| C000247081 [Member] | US Government Corporations and Agencies Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
56.20%
|
| C000247081 [Member] | US Government Debt Securities Quality [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.30%
|
| C000247081 [Member] | Financial Services Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
7.00%
|
| C000247081 [Member] | Healthcare Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
2.50%
|
| C000247081 [Member] | Communications Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
3.10%
|
| C000247081 [Member] | Information Technology Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.60%
|
| C000247081 [Member] | Utilities Sector [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.60%
|
| C000247081 [Member] | Short term investments and other [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
1.70%
|
| C000247081 [Member] | US Government Debt Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
26.30%
|
| C000247081 [Member] | US Government Corporations and Agencies Securities [Member] |
|
| Holdings [Line Items] |
|
| Percent of Net Asset Value |
56.20%
|