Class I [Member] Expense Example - Class I - AMG Yacktman Fund - Class I	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 72
Expense Example, with Redemption, 3 Years	224
Expense Example, with Redemption, 5 Years	390
Expense Example, with Redemption, 10 Years	$ 871

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