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Claim and Claim Adjustment Expense Reserves (Specialty - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - Specialty - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Medical Professional Liability	$ (2)	$ 0	$ (2)	$ 9
Other Professional Liability and Management Liability	17	(1)	17	(1)
Surety	(8)	(7)	(26)	(7)
Warranty	0	0	13	(9)
Other	(10)	4	(10)	4
Total pretax (favorable) unfavorable development	$ (3)	$ (4)	$ (8)	$ (4)

X

- Definition

Net prior year claim and allocated claim adjustment expense reserve development, Medical Professional Liability

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- Definition

Net prior year claim and allocated claim adjustment expense reserve development, Other

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- Definition

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

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- Definition

Net prior year claim and allocated claim adjustment expense reserve development, Surety

+ References

No definition available.

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- Definition

Net prior year claim and allocated claim adjustment expense reserve development, Warranty

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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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