Loans Collectively Evaluated for Impairment (Detail) (Residential Loans, USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Residential Loans
Financing Receivable, Impaired [Line Items]
Principal balance	$ 1,539,330	$ 1,762,165
Recorded investment	1,553,147	1,779,161
Related allowance	$ 20,580	$ 24,762

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

No definition available.

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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

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

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- Definition

The balance of financing receivables 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

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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