Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011 Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses [Member]	Sep. 30, 2011 Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses [Member] Insurance Loss Recoverable [Member]	Sep. 30, 2011 Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses [Member] Recoveries On Unpaid Losses [Member]	Sep. 30, 2011 Non Variable Interest Entities [Member]	Dec. 31, 2010 Non Variable Interest Entities [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Gross Reserve as of beginning balance, Insurance Loss Recoverable		$ 2,531		$ 2,770	$ 2,531
Gross Reserve as of beginning balance, Recoveries on Unpaid Losses			896
Gross Reserve as of beginning balance, Total	3,427
Collections for Cases with Recoveries	(5)	(5)
Accretion of Recoveries	61	48	13
Changes in Discount Rates	107	47	60
Changes in Timing of Collections
Changes in Amount of Collections	(175)	(175)
Changes in Assumptions	18	315	(297)
Changes in LAE Recoveries	24	9	15
Gross Reserve as of ending balance, Insurance Loss Recoverable		2,770		2,770	2,531
Gross Reserve as of ending balance, Recoveries on Unpaid Losses			687
Gross Reserve as of ending balance, Total	$ 3,457

Cash receipts related to recoveries of previously paid claims

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Gross reserve, recoveries on unpaid losses

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Increase Decrease In Loss Adjustment Expense Recoveries

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

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Insurance loss recoverable and changes in recoveries of unpaid losses.

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

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

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

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

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

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Loss And Loss Adjustment Expense Reserves [Line Items]

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