Principles of Consolidation - Assets and Liabilities of Consolidated Variable Interest Entity's (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018 USD ($) Investment	Dec. 31, 2017 USD ($) Investment
Variable Interest Entity [Line Items]
Assets	$ 2,082,771	$ 1,259,774
Liabilities	1,935,299	1,167,157
Sequoia
Variable Interest Entity [Line Items]
Assets	2,082,771	1,259,774
Liabilities	$ 1,935,299	$ 1,167,157
Number of VIEs (in investments) \| Investment	24	22
Sequoia \| Residential loans held-for-investment, at Redwood
Variable Interest Entity [Line Items]
Assets	$ 2,073,174	$ 1,252,879
Sequoia \| Restricted cash
Variable Interest Entity [Line Items]
Assets	157	151
Sequoia \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	6,791	3,391
Sequoia \| REO
Variable Interest Entity [Line Items]
Assets	2,649	3,353
Sequoia \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	5,627	2,568
Sequoia \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	10	4
Sequoia \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	1,929,662	1,164,585
Legacy Sequoia
Variable Interest Entity [Line Items]
Assets	595,660	637,184
Liabilities	$ 582,824	$ 622,982
Number of VIEs (in investments) \| Investment	20	20
Legacy Sequoia \| Residential loans held-for-investment, at Redwood
Variable Interest Entity [Line Items]
Assets	$ 592,029	$ 632,817
Legacy Sequoia \| Restricted cash
Variable Interest Entity [Line Items]
Assets	147	147
Legacy Sequoia \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	835	867
Legacy Sequoia \| REO
Variable Interest Entity [Line Items]
Assets	2,649	3,353
Legacy Sequoia \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	589	537
Legacy Sequoia \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	0	0
Legacy Sequoia \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	582,235	622,445
Sequoia Choice
Variable Interest Entity [Line Items]
Assets	1,487,111	622,590
Liabilities	$ 1,352,475	$ 544,175
Number of VIEs (in investments) \| Investment	4	2
Sequoia Choice \| Residential loans held-for-investment, at Redwood
Variable Interest Entity [Line Items]
Assets	$ 1,481,145	$ 620,062
Sequoia Choice \| Restricted cash
Variable Interest Entity [Line Items]
Assets	10	4
Sequoia Choice \| Accrued interest receivable
Variable Interest Entity [Line Items]
Assets	5,956	2,524
Sequoia Choice \| REO
Variable Interest Entity [Line Items]
Assets	0	0
Sequoia Choice \| Accrued interest payable
Variable Interest Entity [Line Items]
Liabilities	5,038	2,031
Sequoia Choice \| Accrued expenses and other liabilities
Variable Interest Entity [Line Items]
Liabilities	10	4
Sequoia Choice \| Asset-backed securities issued
Variable Interest Entity [Line Items]
Liabilities	$ 1,347,427	$ 542,140

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=108788376&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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