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Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable) (Detail) - Insurance Loss Recoverable [Member] $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($)
Roll forward of Insurance Loss Recoverable [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	$ 1,694
Collections for Cases	(25)
Accretion of Recoveries	9
Changes in Discount Rates	156
Changes in Assumptions	(291)	[1]
Gross Reserve ending balance, Insurance loss recoverable	$ 1,543
[1] Includes amounts related to paid claims and LAE that are expected to be recovered in the future.

X

- Definition

Cash receipts related to recoveries of previously paid claims

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No definition available.

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X

- 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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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Roll forward of Insurance Loss Recoverable [Line Items]

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No definition available.

+ Details

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- Details

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Period Type: