Annual Total Returns - Class R |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
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 |
Dec. 31, 2015 |
|
| ARBITRAGE FUND | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 2.62% | 5.94% | (1.02%) | 0.85% | 5.43% | 3.56% | 2.12% | 2.60% | 3.38% | 0.61% |
| WATER ISLAND EVENT-DRIVEN FUND | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 1.91% | 5.63% | (0.82%) | 0.91% | 13.02% | 4.52% | (0.34%) | 3.68% | 5.06% | (8.31%) |
| WATER ISLAND CREDIT OPPORTUNITIES FUND | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 5.23% | 7.01% | (2.93%) | 3.06% | 6.41% | 5.28% | 1.69% | 1.16% | 4.72% | (1.26%) |