Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entity's (Detail) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016 USD ($) Investment	Dec. 31, 2015 USD ($) Investment
Variable Interest Entity [Line Items]
Assets	$ 888,026	$ 1,195,574
Liabilities	$ 860,256	$ 1,050,861
Number of VIEs \| Investment	21	22
Sequoia
Variable Interest Entity [Line Items]
Assets	$ 887,895	$ 1,028,124
Liabilities	$ 860,156	$ 997,475
Number of VIEs \| Investment	20	21
Commercial Securitization
Variable Interest Entity [Line Items]
Assets	$ 131	$ 167,450
Liabilities	$ 100	$ 53,386
Number of VIEs \| Investment	1	1
Residential Loans Held for Investment
Variable Interest Entity [Line Items]
Assets	$ 880,197	$ 1,021,870
Residential Loans Held for Investment \| Sequoia
Variable Interest Entity [Line Items]
Assets	880,197	1,021,870
Residential Loans Held for Investment \| Commercial Securitization
Variable Interest Entity [Line Items]
Assets	0	0
Commercial Loans Held For Investment
Variable Interest Entity [Line Items]
Assets		166,016
Commercial Loans Held For Investment \| Sequoia
Variable Interest Entity [Line Items]
Assets		0
Commercial Loans Held For Investment \| Commercial Securitization
Variable Interest Entity [Line Items]
Assets		166,016
Restricted cash
Variable Interest Entity [Line Items]
Assets	278	365
Restricted cash \| Sequoia
Variable Interest Entity [Line Items]
Assets	147	228
Restricted cash \| Commercial Securitization
Variable Interest Entity [Line Items]
Assets	131	137
Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	1,058	2,428
Accrued interest receivable \| Sequoia
Variable Interest Entity [Line Items]
Assets	1,058	1,131
Accrued interest receivable \| Commercial Securitization
Variable Interest Entity [Line Items]
Assets	0	1,297
Other Assets
Variable Interest Entity [Line Items]
Assets	6,493	4,895
Other Assets \| Sequoia
Variable Interest Entity [Line Items]
Assets	6,493	4,895
Other Assets \| Commercial Securitization
Variable Interest Entity [Line Items]
Assets	0	0
Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	628	804
Accrued interest payable \| Sequoia
Variable Interest Entity [Line Items]
Liabilities	528	555
Accrued interest payable \| Commercial Securitization
Variable Interest Entity [Line Items]
Liabilities	100	249
Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities		100
Accrued expenses and other liabilities \| Sequoia
Variable Interest Entity [Line Items]
Liabilities		100
Accrued expenses and other liabilities \| Commercial Securitization
Variable Interest Entity [Line Items]
Liabilities		0
Asset-backed Securities
Variable Interest Entity [Line Items]
Liabilities	859,628	1,049,957
Asset-backed Securities \| Sequoia
Variable Interest Entity [Line Items]
Liabilities	859,628	996,820
Asset-backed Securities \| Commercial Securitization
Variable Interest Entity [Line Items]
Liabilities	$ 0	$ 53,137

Number of Variable Interest Entities, Acquired and Consolidated

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5710-111685

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

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+ References

No definition available.

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