Secured Financings - Summary of Key Terms of Revolving Repurchase Facilities (Detail)	12 Months Ended
Dec. 31, 2014
MetLife [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+1.81 %
Rate	1.81%
Guarantee	50.00%
Advance Rate	77.27%
Margin Call	Collateral marks only
Term/Maturity	June 29, 2020
Wells Fargo [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+1.82 %
Rate	1.82%
Guarantee	25.00%
Advance Rate	78.82%
Margin Call	Collateral marks only
Term/Maturity	Term matched
Citibank [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+1.93 %
Rate	1.93%
Guarantee	25.00%
Advance Rate	76.68%
Margin Call	Collateral marks only
Term/Maturity	Term matched
Bank of America [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+1.77 %
Rate	1.77%
Guarantee	50.00%
Advance Rate	79.59%
Margin Call	Collateral marks only
Term/Maturity	May 21, 2019
JP Morgan [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+1.94 %
Rate	1.94%
Guarantee	25.00%
Advance Rate	77.92%
Margin Call	Collateral marks only
Term/Maturity	Term matched
Morgan Stanley [Member]
Line of Credit Facility [Line Items]
LIBOR basis spread on debt obligation	L+2.32 %
Rate	2.32%
Guarantee	25.00%
Advance Rate	78.71%
Margin Call	Collateral marks only
Term/Maturity	March 3, 2017

Debt Instrument Revolving Repurchase Facilities Advance Rate

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- Definition

Debt Instrument Revolving Repurchase Facilities Guarantee Rate

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Revolving Repurchase Facilities Margin Call Description

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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