Fair Value of Financial Instruments - Portion of Net Gains (Losses) Attributable to Level 3 Assets and Liabilities Still Held Included in Net Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loan purchase and interest rate lock commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 liability	$ (14)	$ (503)	$ (577)
Non-controlling interest in consolidated HEI entity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 liability	(5,294)	(396)	0
Net investments in HEI securitization entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	8,210	614	0
Residential loans, held-for-investment, at fair value | Residential loans at Redwood
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(43,019)	5,886	1,138
Residential loans, held-for-investment, at fair value | Net investments in consolidated Sequoia entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(25,563)	12,455	(14,646)
Residential loans, held-for-investment, at fair value | Freddie Mac SLST
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(76,811)	62,124	(21,220)
Business purpose loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(31,927)	9,444	9,420
Multifamily securities | Freddie Mac K-Series
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	110	11,599	(9,309)
Single-family rental loans | CAFL
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(34,899)	8,198	(37,062)
Trading securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(34,027)	738	(83,327)
AFS Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(2,540)	0	(388)
Servicer advance investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(11,076)	(926)	(8,902)
MSRs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	9,804	629	(17,545)
Excess MSRs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(5,196)	(8,017)	(8,302)
Shared home appreciation options
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(670)	212	(1,884)
Other investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	(901)	(6)	(285)
Loan purchase and interest rate lock commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net gain (loss) attributable to Level 3 asset	$ 336	$ 4,633	$ 15,027