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Loss and Loss Adjustment Expense Reserves (Schedule of Insurance Loss Recoverable) (Detail) - Insurance Loss Recoverable [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Roll forward of Insurance Loss Recoverable [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	$ 183	$ 137
Collections for Cases	(16)	(8)
Accretion of Recoveries	7	6
Changes in Discount Rates	0	0
Changes in Assumptions	11	48
Gross Reserve ending balance, Insurance loss recoverable	$ 185	$ 183

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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.

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- 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]

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