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Loss and Loss Adjustment Expense Reserves (Schedule of Insurance Loss Recoverable) (Detail) - Insurance Loss Recoverable [Member] $ in Millions	9 Months Ended
	Sep. 30, 2025 USD ($)
Roll forward of Insurance Loss Recoverable [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	$ 185
Collections for Cases	(232)
Accretion of Recoveries	6
Changes in Discount Rates	2
Changes in Assumptions	78
Gross Reserve ending balance, Insurance loss recoverable	$ 39

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- Definition

Cash receipts related to recoveries of previously paid claims

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- Definition

Carrying amount as of the balance sheet date of paid insurance policy claims and LAE expense expected to be recovered.

+ References

No definition available.

+ Details

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X

- Definition

Insurance Loss Recoverable And Changes In Recoveries Of Unpaid Losses Accretion Of Recoveries

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- Definition

Insurance Loss Recoverable And Changes In Recoveries Of Unpaid Losses Change In Assumptions

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- Definition

Insurance Loss Recoverable And Changes In Recoveries Of Unpaid Losses Change In Discount Rate

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- Definition

Roll forward of Insurance Loss Recoverable [Line Items]

+ References

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- Details

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