Principles of Consolidation - Summary of Unconsolidated Variable Interest Entity's Sponsored by Redwood (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Debt securities, available for sale	$ 206,792	$ 218,458
Variable Interest Entity, Not Primary Beneficiary
Assets
Maximum loss exposure	152,206	165,870
Assets transferred:
Principal balance of loans outstanding	4,959,234	7,728,432
Principal balance of loans 30+ days delinquent	30,594	138,029
Interest-only, senior and subordinate securities, classified as trading \| Variable Interest Entity, Not Primary Beneficiary
Assets
Debt securities, trading	18,214	20,982
Subordinate securities, classified as AFS \| Variable Interest Entity, Not Primary Beneficiary
Assets
Debt securities, available for sale	127,542	136,475
Mortgage servicing rights
Assets
Servicing asset, fair value	12,438	8,815
Mortgage servicing rights \| Variable Interest Entity, Not Primary Beneficiary
Assets
Servicing asset, fair value	$ 6,450	$ 8,413

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