S000001129 [Member] Investment Objectives and Goals - AMG River Road Dividend All Cap Value Fund	Oct. 31, 2025
Prospectus [Line Items]
Risk/Return [Heading]	AMG River Road Dividend All Cap Value Fund
Objective [Heading]	Investment Objective
Objective, Primary [Text Block]	The Fund seeks to provide high current income and,
Objective, Secondary [Text Block]	secondarily, long-term capital appreciation.

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