Financing Agreements - Financing Agreements (Details) $ in Thousands		3 Months Ended	6 Months Ended
	Apr. 04, 2022	Mar. 31, 2023	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Financing Agreements [Line Items]
Unpaid Principal Balance			$ 7,789,487	$ 7,043,944
Fair Value / Carrying Value			$ 7,568,177	$ 6,812,086
Weighted average fixed rate for Senior Bonds issued			3.96%	3.70%
Stock split ratio, common stock	0.25
Agreements with mark-to-market collateral provisions
Financing Agreements [Line Items]
Unpaid Principal Balance			$ 2,403,374	$ 2,223,298
Fair Value / Carrying Value			$ 2,402,444	$ 2,223,047
Weighted average fixed rate for Senior Bonds issued			6.87%	5.73%
Agreements with mark-to-market collateral provisions | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			$ 865,655
Agreements with mark-to-market collateral provisions | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			88,389
Agreements with mark-to-market collateral provisions | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			480,381
Fair Value / Carrying Value			$ 311,200
Extension period			1 year
Agreements with mark-to-market collateral provisions | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			$ 968,949
Fair Value / Carrying Value			681,100
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance			1,939,310	$ 2,111,647
Fair Value / Carrying Value			$ 1,938,380	$ 2,111,396
Weighted average fixed rate for Senior Bonds issued			7.17%	5.74%
Weighted Average Term To Maturity (Months)		6 months 27 days	9 months 3 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			$ 553,200
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			401,591
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			88,389
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			480,381
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			968,949
Agreements with mark-to-market collateral provisions | Securitized debt
Financing Agreements [Line Items]
Unpaid Principal Balance			464,064	$ 111,651
Fair Value / Carrying Value			$ 464,064	$ 111,651
Weighted average fixed rate for Senior Bonds issued			5.67%	5.47%
Weighted Average Term To Maturity (Months)		1 month 15 days	15 days
Agreements with mark-to-market collateral provisions | Securitized debt | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			$ 464,064
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			553,200	$ 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			968,546	1,004,260
Fair Value / Carrying Value			$ 967,884	$ 1,003,604
Weighted average fixed rate for Senior Bonds issued			7.61%	6.53%
Weighted Average Term To Maturity (Months)		16 months 24 days	13 months 9 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			$ 440,100
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			491,160
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			13,033
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			0
Agreements with Non-mark-to-market Collateral Provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance			464,353
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			440,100	884,500
Securitized debt | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance			4,187,578	3,586,397
Fair Value / Carrying Value			$ 3,969,274	$ 3,357,590
Weighted average fixed rate for Senior Bonds issued			3.88%	3.33%
Securitized debt | Residential Whole Loans and REO | Held at Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value			$ 3,100,000
Securitized debt | Estimated Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value				$ 2,400,000
Weighted average fixed rate for Senior Bonds issued				0.84%
Financing agreements, amortized cost			3,300,000	$ 2,600,000
Convertible senior notes | Unsecured
Financing Agreements [Line Items]
Unpaid Principal Balance			229,989	229,989
Fair Value / Carrying Value			$ 228,575	$ 227,845
Weighted average fixed rate for Senior Bonds issued			6.94%	6.94%
Weighted Average Term To Maturity (Months)		17 months 15 days	11 months 15 days
Impact of Net Swap Carry | Unsecured
Financing Agreements [Line Items]
Weighted average fixed rate for Senior Bonds issued			(1.38%)	(0.84%)