Repurchase Agreements - Summary of Repurchase Agreements (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($)
Debt Instrument [Line Items]
Outstanding Balance	$ 169,583
Citi MRA [Member]
Debt Instrument [Line Items]
Security Interests	CMBS
Maturity Dates	7/17/17 - 8/30/2017
Outstanding Balance	$ 153,567
Prepayment Provisions	None
Citi MRA [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest Rate	1.30%
Citi MRA [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest Rate	1.60%
RBC MRA [Member]
Debt Instrument [Line Items]
Security Interests	CMBS
Maturity Dates	7/28/2017
Outstanding Balance	$ 16,016
Prepayment Provisions	None
RBC MRA [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Interest Rate	1.25%

Debt instrument prepayment provisions.

No definition available.

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- Definition

Repurchase agreements, security interests.

+ References

No definition available.

+ Details

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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

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.

+ References

No definition available.

+ Details

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- Definition

This describes the time frame of the terms of the entity's repurchase agreements.

+ References

+ Details

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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 55
-Paragraph 51
-URI http://asc.fasb.org/extlink&oid=77903054&loc=d3e101761-111710

+ Details

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