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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	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Commercial	$ (13)	$ 0	$ (7)	$ (5)
Specialty	11	0	2	22
Other	0	0	0	(2)
Total pretax (favorable) unfavorable development	$ (2)	$ 0	$ (5)	$ 15

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- Definition

Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve, Commercial

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- Definition

Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve, Other

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- Definition

Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve, Specialty

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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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- 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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