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Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Details) (USD $) In Millions	6 Months Ended
	Jun. 30, 2011 Insurance Loss Recoverable and Changes in Recoveries on Unpaid Losses [Member]	Jun. 30, 2011 Insurance Loss Recoverable and Changes in Recoveries on Unpaid Losses [Member] Insurance Loss Recoverable [Member]	Jun. 30, 2011 Insurance Loss Recoverable and Changes in Recoveries on Unpaid Losses [Member] Unpaid Losses [Member]	Jun. 30, 2011 Non Variable Interest Entities [Member]	Dec. 31, 2010 Non Variable Interest Entities [Member]
Gross Reserve as of beginning balance, Insurance Loss Recoverable		$ 2,531		$ 2,658	$ 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	(3)	(3)
Accretion of Recoveries	44	34	10
Changes in Discount Rates	22	20	2
Changes in Timing of Collections
Changes in Amount of Collections	(116)	(116)
Changes in Assumptions	(22)	190	(212)
Changes in LAE Recoveries	7	2	5
Gross Reserve as of ending balance, Insurance Loss Recoverable		2,658		2,658	2,531
Gross Reserve as of ending balance, Recoveries on Unpaid Losses			701
Gross Reserve as of ending balance, Total	$ 3,359

X

- Definition

Gross reserve, recoveries on unpaid losses

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X

- Definition

Increase Decrease In Loss Adjustment Expense Recoveries

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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.

+ Details

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X

- Definition

Insurance loss recoverable and changes in recoveries of unpaid losses.

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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 Collections

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- Definition

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

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- Definition

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

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X

- Definition

The collections in the period which reduce the recorded receivable pertaining to a loss contingency accrual.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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