Equity Compensation Plans - Unrecognized Compensation Cost (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized compensation cost at beginning of period	$ 27,664
Equity grants	29,237
Performance-based valuation adjustment	1,072
Equity grant forfeitures	(1,247)
Equity compensation expense	(14,343)
Unrecognized Compensation Cost at End of Period	42,383
Restricted Stock Awards
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized Compensation Cost at End of Period	100
Restricted Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized Compensation Cost at End of Period	4,000
Deferred Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized Compensation Cost at End of Period	26,000
Performance Stock Units
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Roll Forward]
Unrecognized Compensation Cost at End of Period	12,000
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	564
Equity grants	0
Performance-based valuation adjustment	0
Equity grant forfeitures	(2)
Equity compensation expense	(478)
Unrecognized Compensation Cost at End of Period	84
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	3,540
Equity grants	2,371
Performance-based valuation adjustment	0
Equity grant forfeitures	(695)
Equity compensation expense	(1,627)
Unrecognized Compensation Cost at End of Period	3,589
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	17,766
Equity grants	18,380
Performance-based valuation adjustment	0
Equity grant forfeitures	(550)
Equity compensation expense	(9,123)
Unrecognized Compensation Cost at End of Period	26,473
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	5,794
Equity grants	8,125
Performance-based valuation adjustment	1,072
Equity grant forfeitures	0
Equity compensation expense	(2,754)
Unrecognized Compensation Cost at End of Period	12,237
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	361
Performance-based valuation adjustment	0
Equity grant forfeitures	0
Equity compensation expense	(361)
Unrecognized Compensation Cost at End of Period	$ 0

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]

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- Definition

Represents the amount of equity grant forfeitures during the period.

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- Definition

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

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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