Loans Collectively Evaluated for Impairment (Detail) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Financing Receivable, Impaired [Line Items]
Unpaid principal balance	$ 3,870,056	$ 3,801,921
Recorded investment	3,908,849	3,844,372
Related allowance	$ 58,558	$ 57,804

The recorded investment in financing receivables that were collectively evaluated for impairment.

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524
-Subparagraph (g)

+ Details

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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- Definition

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.

+ Details

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