Class N [Member] Expense Example	Dec. 31, 2025 USD ($)
Class N and Class Z \| AMG Yacktman Fund \| Class N
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 104
Expense Example, with Redemption, 3 Years	325
Expense Example, with Redemption, 5 Years	563
Expense Example, with Redemption, 10 Years	1,248
Class N and Class Z \| AMG Yacktman Fund \| Class Z
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	63
Expense Example, with Redemption, 3 Years	199
Expense Example, with Redemption, 5 Years	346
Expense Example, with Redemption, 10 Years	774
Class N [Member] \| AMG Yacktman Special Opportunities Fund \| Class N
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	128
Expense Example, with Redemption, 3 Years	467
Expense Example, with Redemption, 5 Years	830
Expense Example, with Redemption, 10 Years	$ 1,851

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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