Shareholders' Equity - Preferred stock authorized for issuance (Details)	Sep. 30, 2025 shares
Voting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, shares authorized (shares)	12,500,000
Nonvoting Preferred Stock
Class of Stock [Line Items]
Preferred Stock, shares authorized (shares)	12,500,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

AMERICAN FINANCIAL GROUP INC 10-Q