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Loss And Loss Adjustment Expense Reserves (Schedule Of Total Estimated Recoveries From Ineligible Mortgage Loans) (Details) (Ineligible Mortgage Loans [Member], USD $) In Millions	6 Months Ended
	Jun. 30, 2011
Ineligible Mortgage Loans [Member]
Total Estimated Recoveries from Ineligible loans as of Beginning Balance	$ 2,517
Accretion of Future Collections	38
Changes in Discount Rates	12
Recoveries (Collections)
Changes in Assumptions	174
Total Estimated Recoveries from Ineligible loans as of Ending Balance	$ 2,741

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- Definition

Estimated Insurance Recoveries Accretion Of Future Collections

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Balance Type:	debit
Period Type:	duration

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- Definition

Estimated Insurance Recoveries Change In Assumptions

+ Details

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Balance Type:	debit
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- Definition

Estimated Insurance Recoveries Change In Discount Rate

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- Definition

Estimated Insurance Recoveries Recoveries

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X

- Definition

Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 17
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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