v3.25.3

Segments of Operations - Components of underwriting profit, including significant segment expenses by segment and sub-segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Net earned premiums	$ 2,013	$ 2,055	$ 5,240	$ 5,186
Losses and loss adjustment expenses	1,355	1,430	3,327	3,279
Commissions and other underwriting expenses	529	518	1,593	1,527
Operating segments \| Property and Casualty Insurance
Segment Reporting Information [Line Items]
Net earned premiums	2,013	2,055	5,240	5,186
Losses and loss adjustment expenses	1,355	1,430	3,327	3,274
Commissions and other underwriting expenses	520	510	1,568	1,494
Property and casualty insurance underwriting profit	138	115	345	418
Operating segments \| Property and transportation \| Property and Casualty Insurance
Segment Reporting Information [Line Items]
Net earned premiums	935	989	2,011	2,061
Losses and loss adjustment expenses	728	784	1,426	1,441
Commissions and other underwriting expenses	152	172	466	487
Property and casualty insurance underwriting profit	55	33	119	133
Operating segments \| Specialty casualty \| Property and Casualty Insurance
Segment Reporting Information [Line Items]
Net earned premiums	810	797	2,403	2,371
Losses and loss adjustment expenses	541	519	1,593	1,504
Commissions and other underwriting expenses	236	215	708	657
Property and casualty insurance underwriting profit	33	63	102	210
Operating segments \| Specialty financial \| Property and Casualty Insurance
Segment Reporting Information [Line Items]
Net earned premiums	268	269	826	754
Losses and loss adjustment expenses	85	125	306	325
Commissions and other underwriting expenses	132	123	394	350
Property and casualty insurance underwriting profit	51	21	126	79
Operating segments \| Other lines \| Property and Casualty Insurance
Segment Reporting Information [Line Items]
Losses and loss adjustment expenses	1	2	2	4
Property and casualty insurance underwriting profit	$ (1)	$ (2)	$ (2)	$ (4)

Underwriting income (loss) for the property and casualty insurance segment, which is calculated as premiums earned less losses and loss adjustment expenses less commissions and other underwriting expenses.

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Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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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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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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AMERICAN FINANCIAL GROUP INC 10-Q