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Loss And Loss Adjustment Expense Reserves (Schedule Of Total Estimated Recoveries From Ineligible Second-Lien Mortgage Loans) (Detail) (Ineligible Mortgage Loans [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Ineligible Mortgage Loans [Member]
Loss And Loss Adjustment Expense Reserves [Line Items]
Total Estimated Recoveries from Ineligible Mortgage Loans as of December 31, 2011	$ 3,119
Accretion of Future Collections	34
Changes in Discount Rates	2
Recoveries (Collections)
Changes in Amount of Collections
Changes in Assumptions	92
Total Estimated Recoveries from Ineligible Mortgage Loans as of September 30, 2012	$ 3,247

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- Definition

Estimated Insurance Changes In Amount Of Collections

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- Definition

Estimated Insurance Recoveries Accretion Of Future Collections

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- Definition

Estimated Insurance Recoveries Change In Assumptions

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- Definition

Estimated Insurance Recoveries Change In Discount Rate

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- Definition

Estimated Insurance Recoveries Collections

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- 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 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



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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