Secured Debt Agreements, Net - Schedule of Secured Debt Agreements (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	$ 8,996,481,000	$ 5,290,536,000
Deferred financing costs	(21,725,000)	(16,681,000)
Secured debt agreements borrowings outstanding	1,538,548,000	518,864,000
Net book value of secured debt	8,974,756,000	5,273,855,000
Credit Facilities [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	6,903,683,000	4,068,249,000
Asset-Specific Financings [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	1,538,548,000	518,864,000
GE Portfolio Acquisition Facility [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	510,405,000	703,423,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Secured debt agreements borrowings outstanding	$ 43,845,000	$ 0

Secured Debt Repurchase Agreements Face Amount

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- Definition

Secured Debt Repurchase Agreements Gross

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 55
-Paragraph 51
-URI http://asc.fasb.org/extlink&oid=109221364&loc=d3e101761-111710

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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