Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entity's (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Investment	Dec. 31, 2016 USD ($) Investment
Variable Interest Entity [Line Items]
Assets	$ 1,259,774	$ 798,317
Liabilities	1,167,157	773,980
Legacy Sequoia
Variable Interest Entity [Line Items]
Assets	637,184	798,317
Liabilities	$ 622,982	$ 773,980
Number of VIEs \| Investment	20	20
Legacy Sequoia \| Residential loans, held-for-investment
Variable Interest Entity [Line Items]
Assets	$ 632,817	$ 791,636
Legacy Sequoia \| Restricted cash
Variable Interest Entity [Line Items]
Assets	147	148
Legacy Sequoia \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	867	1,000
Legacy Sequoia \| REO
Variable Interest Entity [Line Items]
Assets	3,353	5,533
Legacy Sequoia \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	537	518
Legacy Sequoia \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	0
Legacy Sequoia \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	622,445	773,462
Sequoia Choice
Variable Interest Entity [Line Items]
Assets	622,590	0
Liabilities	$ 544,175	$ 0
Number of VIEs \| Investment	2	0
Sequoia Choice \| Residential loans, held-for-investment
Variable Interest Entity [Line Items]
Assets	$ 620,062	$ 0
Sequoia Choice \| Restricted cash
Variable Interest Entity [Line Items]
Assets	4	0
Sequoia Choice \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	2,524	0
Sequoia Choice \| REO
Variable Interest Entity [Line Items]
Assets	0	0
Sequoia Choice \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	2,031	0
Sequoia Choice \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	4
Sequoia Choice \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	542,140	0
Total Consolidated VIEs
Variable Interest Entity [Line Items]
Assets	1,259,774	798,317
Liabilities	$ 1,167,157	$ 773,980
Number of VIEs \| Investment	22	20
Total Consolidated VIEs \| Residential loans, held-for-investment
Variable Interest Entity [Line Items]
Assets	$ 1,252,879	$ 791,636
Total Consolidated VIEs \| Restricted cash
Variable Interest Entity [Line Items]
Assets	151	148
Total Consolidated VIEs \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	3,391	1,000
Total Consolidated VIEs \| REO
Variable Interest Entity [Line Items]
Assets	3,353	5,533
Total Consolidated VIEs \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	2,568	518
Total Consolidated VIEs \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	4
Total Consolidated VIEs \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	$ 1,164,585	$ 773,462

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=64801991&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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