Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable) (Detail) - Insurance Loss Recoverable [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Roll forward of Insurance Loss Recoverable [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	$ 1,677	$ 1,694
Collections for Cases	(266)	(49)
Accretion of Recoveries	15	14
Changes in Discount Rates	25	115
Changes in Assumptions	(155)	(97)
Gross Reserve ending balance, Insurance loss recoverable	$ 1,296	$ 1,677

Cash receipts related to recoveries of previously paid claims

No definition available.

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

No definition available.

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

No definition available.

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

No definition available.

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

No definition available.

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Roll forward of Insurance Loss Recoverable [Line Items]

No definition available.

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