Financing Agreements - Financing Agreements (Details) $ in Thousands		3 Months Ended	12 Months Ended
	Apr. 04, 2022	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Financing Agreements [Line Items]
Unpaid Principal Balance		$ 7,282,912	$ 7,043,944
Fair Value / Carrying Value		$ 7,101,318	$ 6,812,086
Weighted Average Cost of Funding		3.95%	3.70%
Stock split ratio, common stock	0.25
Convertible Debt | 6.25% Convertible Senior Notes
Financing Agreements [Line Items]
Stock split ratio, common stock	0.25
Agreements with mark-to-market collateral provisions
Financing Agreements [Line Items]
Unpaid Principal Balance		$ 2,097,281	$ 2,223,298
Fair Value / Carrying Value		$ 2,096,796	$ 2,223,047
Weighted Average Cost of Funding		6.54%	5.73%
Agreements with mark-to-market collateral provisions | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		$ 608,180
Agreements with mark-to-market collateral provisions | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		646,122
Agreements with mark-to-market collateral provisions | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		593,862
Fair Value / Carrying Value		$ 249,100
Extension period		1 year
Agreements with mark-to-market collateral provisions | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		$ 249,117
Fair Value / Carrying Value		608,200
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance		1,692,254	$ 2,111,647
Fair Value / Carrying Value		$ 1,691,769	$ 2,111,396
Weighted Average Cost of Funding		6.67%	5.74%
Weighted Average Term To Maturity (Months)		8 months 3 days	6 months 27 days
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | Not Held at Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value		$ 680,700
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		203,153
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		646,122
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		593,862
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		249,117
Agreements with mark-to-market collateral provisions | Securitized debt
Financing Agreements [Line Items]
Unpaid Principal Balance		405,027	$ 111,651
Fair Value / Carrying Value		$ 405,027	$ 111,651
Weighted Average Cost of Funding		5.56%	5.47%
Weighted Average Term To Maturity (Months)		1 month 3 days	1 month 15 days
Agreements with mark-to-market collateral provisions | Securitized debt | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		$ 405,027
Agreements with mark-to-market collateral provisions | Securitized debt | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		0
Agreements with mark-to-market collateral provisions | Securitized debt | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		0
Agreements with mark-to-market collateral provisions | Securitized debt | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		0
Agreements with mark-to-market collateral provisions | Estimated Fair Value
Financing Agreements [Line Items]
Financing agreements, amortized cost		680,700	$ 578,900
Agreements with mark-to-market collateral provisions | Estimated Fair Value | Held at Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value			578,900
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance		946,573	1,004,260
Fair Value / Carrying Value		$ 946,006	$ 1,003,604
Weighted Average Cost of Funding		7.31%	6.53%
Weighted Average Term To Maturity (Months)		13 months 9 days	16 months 24 days
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | Held at Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value		$ 526,600
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		216,555
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		361,202
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		11,526
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance		357,290
Agreements with Non-mark-to-market Collateral Provisions | Estimated Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value			$ 884,500
Financing agreements, amortized cost		526,600	884,500
Securitized debt | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance		4,009,069	3,586,397
Fair Value / Carrying Value		$ 3,830,309	$ 3,357,590
Weighted Average Cost of Funding		3.73%	3.33%
Securitized debt | Residential Whole Loans and REO | Held at Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value		$ 2,900,000
Securitized debt | Estimated Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value			$ 2,400,000
Weighted Average Cost of Funding		1.22%	0.84%
Financing agreements, amortized cost		$ 3,100,000	$ 2,600,000
Convertible senior notes | Unsecured
Financing Agreements [Line Items]
Unpaid Principal Balance		229,989	229,989
Fair Value / Carrying Value		$ 228,207	$ 227,845
Weighted Average Cost of Funding		6.94%	6.94%
Weighted Average Term To Maturity (Months)		14 months 15 days	17 months 15 days
Impact of Net Swap Carry | Unsecured
Financing Agreements [Line Items]
Weighted Average Cost of Funding		(1.22%)	(0.84%)