Secured Debt Agreements, Net - Schedule of Secured Debt Agreements (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	$ 530,358,000	$ 679,207,000
Secured debt agreements borrowings outstanding	5,823,766,000	5,731,626,000
Deferred financing costs	(17,729,000)	(15,272,000)
Net book value of secured debt	5,806,037,000	5,716,354,000
Credit Facilities [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	4,014,582,000	3,572,837,000
GE Portfolio Acquisition Facility [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	1,188,076,000	1,479,582,000
Asset-Specific Financings [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	530,358,000	679,207,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	$ 90,750,000	$ 0

Secured Debt Repurchase Agreements Face Amount

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- Definition

Secured Debt Repurchase Agreements Gross

+ References

No definition available.

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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.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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