Principles of Consolidation - Key Assumptions and Sensitivity Analysis for Assets Retained from Unconsolidated Variable Interest Entity's Sponsored by Redwood (Details) - Variable Interest Entity, Not Primary Beneficiary - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
MSRs
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value	$ 11,160	$ 11,589
Expected life (in years)	7 years	7 years
Prepayment speed assumption (annual CPR) (as a percent)	8.00%	8.00%
Decrease in fair value from:
10% adverse change	$ 350	$ 311
25% adverse change	$ 801	$ 779
Discount rate assumption	11.00%	11.00%
Decrease in fair value from:
100 basis point increase	$ 412	$ 430
200 basis point increase	798	832
Senior Securities
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value	$ 31,208	$ 28,722
Expected life (in years)	7 years	7 years
Prepayment speed assumption (annual CPR) (as a percent)	8.00%	10.00%
Decrease in fair value from:
10% adverse change	$ 1,190	$ 970
25% adverse change	$ 2,908	$ 2,344
Discount rate assumption	12.00%	12.00%
Decrease in fair value from:
100 basis point increase	$ 1,120	$ 980
200 basis point increase	$ 2,162	$ 1,894
Credit loss assumption	0.03%	0.03%
Subordinate Securities
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Fair value	$ 77,714	$ 74,367
Expected life (in years)	15 years	16 years
Prepayment speed assumption (annual CPR) (as a percent)	8.00%	8.00%
Decrease in fair value from:
10% adverse change	$ 425	$ 386
25% adverse change	$ 999	$ 907
Discount rate assumption	8.00%	9.00%
Decrease in fair value from:
100 basis point increase	$ 7,553	$ 7,198
200 basis point increase	$ 14,065	$ 13,394
Credit loss assumption	0.03%	0.03%
Decrease in fair value from:
10% higher losses	$ 34	$ 31
25% higher losses	$ 83	$ 76
Minimum | MSRs
Decrease in fair value from:
Impact of adverse change in prepayment speed	10.00%	10.00%
Impact of increase in discount rate assumption	1.00%	1.00%
Impact of adverse change in expected credit losses	10.00%	10.00%
Minimum | Senior Securities
Decrease in fair value from:
Impact of adverse change in prepayment speed	10.00%	10.00%
Impact of increase in discount rate assumption	1.00%	1.00%
Impact of adverse change in expected credit losses	10.00%	10.00%
Minimum | Subordinate Securities
Decrease in fair value from:
Impact of adverse change in prepayment speed	10.00%	10.00%
Impact of increase in discount rate assumption	1.00%	1.00%
Impact of adverse change in expected credit losses	10.00%	10.00%
Maximum | MSRs
Decrease in fair value from:
Impact of adverse change in prepayment speed	25.00%	25.00%
Impact of increase in discount rate assumption	2.00%	2.00%
Impact of adverse change in expected credit losses	25.00%	25.00%
Maximum | Senior Securities
Decrease in fair value from:
Impact of adverse change in prepayment speed	25.00%	25.00%
Impact of increase in discount rate assumption	2.00%	2.00%
Impact of adverse change in expected credit losses	25.00%	25.00%
Maximum | Subordinate Securities
Decrease in fair value from:
Impact of adverse change in prepayment speed	25.00%	25.00%
Impact of increase in discount rate assumption	2.00%	2.00%
Impact of adverse change in expected credit losses	25.00%	25.00%