Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entity's (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017 USD ($) Investment	Dec. 31, 2016 USD ($) Investment
Variable Interest Entity [Line Items]
Assets	$ 713,404	$ 798,317
Liabilities	693,137	773,980
Sequoia
Variable Interest Entity [Line Items]
Assets	713,404	798,317
Liabilities	$ 693,137	$ 773,980
Number of VIEs (in investments) \| Investment	20	20
Sequoia \| Residential loans held-for-investment, at Redwood
Variable Interest Entity [Line Items]
Assets	$ 707,686	$ 791,636
Sequoia \| Restricted cash
Variable Interest Entity [Line Items]
Assets	148	148
Sequoia \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	925	1,000
Sequoia \| Other assets
Variable Interest Entity [Line Items]
Assets	4,645	5,533
Sequoia \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	531	518
Sequoia \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	$ 692,606	$ 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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- Definition

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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- Definition

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+ References

No definition available.

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