Additional Information on Residential Real Estate Loans Held-for-Investment (Detail) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Mortgage Loans on Real Estate [Line Items]
Carrying Value	$ 3,860,233	$ 3,797,095
Residential Real Estate Loans Held for Investment
Mortgage Loans on Real Estate [Line Items]
Principal value	3,882,603	3,815,273
Unamortized premium, net	38,100	42,399
Recorded investment	3,920,703	3,857,672
Allowance for loan losses	(62,306)	(62,432)
Carrying Value	$ 3,858,397	$ 3,795,240

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 47
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The amount of the recorded investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, accounts receivable (with terms exceeding one year), notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reflects the aggregate carrying amount of all consumer loans and leases held in portfolio, net of unearned income and the allowance for losses on consumer loans and leases.

+ References

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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of the contractual principal due at the origination of the mortgage loan (face amount).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reflects the cumulative amount of fees paid by borrowers which have not yet been taken into income and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield.

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