Residential Loans, Net - Recorded Investment in Residential Loans Accounted for Amortized Cost by Credit Quality Indicator (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Recorded investment in residential loans accounted at amortized cost	$ 1,462,013	$ 1,510,756
Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded investment in residential loans accounted at amortized cost	1,376,697	1,407,375
Non-performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded investment in residential loans accounted at amortized cost	$ 85,316	$ 103,381

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953401-111524

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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