Equity Compensation Plans - Unrecognized Compensation Cost (Details) $ in Thousands	9 Months Ended
Sep. 30, 2022 USD ($)
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	$ 42,383
Equity grants	10,796
Performance-based valuation adjustment	(3,205)
Equity grant forfeitures	(554)
Equity compensation expense	(14,824)
Unrecognized Compensation Cost at End of Period	34,596
Redwood Incentive Plan \| Restricted Stock Awards
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	84
Equity grants	0
Performance-based valuation adjustment	0
Equity grant forfeitures	(5)
Equity compensation expense	(79)
Unrecognized Compensation Cost at End of Period	0
Redwood Incentive Plan \| Restricted Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	3,589
Equity grants	2,513
Performance-based valuation adjustment	0
Equity grant forfeitures	(448)
Equity compensation expense	(1,567)
Unrecognized Compensation Cost at End of Period	4,087
Redwood Incentive Plan \| Deferred Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	26,473
Equity grants	7,960
Performance-based valuation adjustment	0
Equity grant forfeitures	(101)
Equity compensation expense	(10,412)
Unrecognized Compensation Cost at End of Period	23,920
Redwood Incentive Plan \| Performance Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	12,237
Equity grants	0
Performance-based valuation adjustment	(3,205)
Equity grant forfeitures	0
Equity compensation expense	(2,524)
Unrecognized Compensation Cost at End of Period	6,508
Employee Stock Purchase Plan
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	0
Equity grants	323
Performance-based valuation adjustment	0
Equity grant forfeitures	0
Equity compensation expense	(242)
Unrecognized Compensation Cost at End of Period	$ 81

Allocated Share-based Compensation Expense, Including Restructuring

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]

+ References

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- Definition

Represents the amount of equity grant forfeitures during the period.

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Valuation Adjustment

+ References

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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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