Amount of the write-down or write-off of a receivable from a reinsurer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on reinsurance recoverable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

Amount of allowance for credit loss on reinsurance recoverable.

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Reinsurance - Reinsurance Recoverable, Allowance for Credit Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance			$ 69
Operating Segments [Member] \| Property, Liability and Casualty Insurance Product Line
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance	$ 68	$ 72	66	$ 72
Reinsurance Recoverable, Credit Loss Expense (Reversal)	1	1	(1)	(3)
Reinsurance, Loss on Uncollectible Accounts in Period, Amount	0	0	0	0
Operating Segments [Member] \| Property, Liability and Casualty Insurance Product Line \| Reinsurance Contract [Axis]: Before Disputed Amounts [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance	22	20	24	24
Operating Segments [Member] \| Property, Liability and Casualty Insurance Product Line \| Reinsurance Contract [Axis]: Disputes [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance	$ 46	$ 52	42	$ 48
Operating Segments [Member] \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance			1
Corporate, Non-Segment [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance			$ 2