Annual Total Returns - Class A |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|---|---|---|---|---|---|---|---|
| MFS Diversified Income Fund | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 9.34% | 5.14% | 9.23% | (13.01%) | 9.30% | 2.15% | 17.38% | (3.69%) | 8.64% | 8.49% |
| MFS Government Securities Fund | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 6.61% | 0.44% | 3.83% | (12.22%) | (2.18%) | 6.24% | 6.19% | 0.27% | 1.91% | 0.52% |
| MFS New Discovery Value Fund | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 2.19% | 9.10% | 10.94% | (11.07%) | 33.45% | 3.40% | 33.27% | (11.34%) | 14.65% | 26.13% |