Cash Received From Reinsurer

No definition available.

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- Definition

Amount of increase (decrease) in deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

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-Name Accounting Standards Codification
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-Subparagraph (a)
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-Publisher FASB
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- Definition

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

+ References

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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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.

+ Details

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- Definition

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

+ References

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

+ References

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- Definition

Amount of allowance for credit loss on reinsurance recoverable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reinsurance - Reinsurance Recoverable, Allowance for Credit Loss (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Sep. 25, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 23, 2026	Dec. 31, 2025	Dec. 31, 2024
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss, Beginning Balance				$ 69
Reinsurance Contract [Axis]: Adverse Development Cover A&E
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Increase (Decrease) in Deferred Revenue				36
Reinsurance and other recoverables						$ 1,437
Reinsurance Contract [Axis]: Adverse Development Cover A&E \| Effect of Commutation Agreement [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Increase (Decrease) in Deferred Revenue		$ 317
Reinsurance and other recoverables						$ 1,120
Cash Received From Reinsurer	$ 1,120
Reinsurance Contract [Axis]: Adverse Development Cover Navigators Group
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Increase (Decrease) in Deferred Revenue			$ (8)		$ (64)
Property, Liability and Casualty Insurance Product Line
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance and other recoverables		5,187	6,627	5,187	6,627		$ 6,723	$ 6,753
Property, Liability and Casualty Insurance Product Line \| Reinsurance Contract [Axis]: Adverse Development Cover Navigators Group
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Increase (Decrease) in Deferred Revenue					(64)
Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance and other recoverables		306	281	306	281		$ 282	$ 282
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		67	72	66	72
Reinsurance Recoverable, Credit Loss Expense (Reversal)		2	1	1	(2)
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		23	21	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		$ 44	$ 51	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