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Claim and Claim Adjustment Expense Reserves (International - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - International - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial	$ (12)	$ (18)	$ (10)
Specialty	6	35	(4)
Other	0	(4)	1
Total pretax (favorable) unfavorable development	$ (6)	$ 13	$ (13)

X

- Definition

Net prior year claim and allocated claim adjustment expense reserve development, Commercial Auto

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X

- Definition

Net Prior Year Claim and Allocated Claim Adjustment Expense Reserve Development, Specialty

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No definition available.

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- Definition

Net Prior Year Claim and Allocated Claim Adjustment Expense Reserve Development, Other Professional Liability

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No definition available.

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- Definition

Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group

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No definition available.

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- Definition

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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No definition available.

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