S000049941 [Member] Expense Example - AMG GW&K SMALL/MID CAP CORE FUND |
Dec. 31, 2025
USD ($)
|
|---|---|
| Class I | |
| Prospectus [Line Items] | |
| Expense Example, with Redemption, 1 Year | $ 89 |
| Expense Example, with Redemption, 3 Years | 278 |
| Expense Example, with Redemption, 5 Years | 482 |
| Expense Example, with Redemption, 10 Years | 1,073 |
| Class N | |
| Prospectus [Line Items] | |
| Expense Example, with Redemption, 1 Year | 109 |
| Expense Example, with Redemption, 3 Years | 340 |
| Expense Example, with Redemption, 5 Years | 590 |
| Expense Example, with Redemption, 10 Years | 1,306 |
| Class Z | |
| Prospectus [Line Items] | |
| Expense Example, with Redemption, 1 Year | 84 |
| Expense Example, with Redemption, 3 Years | 262 |
| Expense Example, with Redemption, 5 Years | 455 |
| Expense Example, with Redemption, 10 Years | $ 1,014 |