Financing Agreements - Financing Agreements (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 8,683,152	$ 7,043,944
Fair Value / Carrying Value	$ 8,536,745	$ 6,812,086
Weighted Average Cost of Funding (in Percent)	4.11%	3.46%
Agreements with mark-to-market collateral provisions
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 2,361,146	$ 2,223,298
Fair Value / Carrying Value	$ 2,360,254	$ 2,223,047
Weighted Average Cost of Funding (in Percent)	6.93%	3.62%
Agreements with mark-to-market collateral provisions | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 1,223,705
Agreements with mark-to-market collateral provisions | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	58,561
Agreements with mark-to-market collateral provisions | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	564,772
Fair Value / Carrying Value	$ 335,200
Extension period	1 year
Agreements with mark-to-market collateral provisions | 6-12 Months | Maximum
Financing Agreements [Line Items]
Extension period	33 months
Agreements with mark-to-market collateral provisions | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 514,108
Fair Value / Carrying Value	945,800
Agreements with mark-to-market collateral provisions | Estimate of Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value		$ 884,500
Financing agreements, amortized cost	178,900	884,500
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance	1,738,543	2,111,647
Fair Value / Carrying Value	$ 1,737,651	$ 2,111,396
Weighted Average Cost of Funding (in Percent)	7.23%	3.63%
Weighted Average Term to Maturity (Months)	11 months 24 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	$ 178,900
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	601,102
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	58,561
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	564,772
Agreements with mark-to-market collateral provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	514,108
Agreements with mark-to-market collateral provisions | Securitized debt
Financing Agreements [Line Items]
Unpaid Principal Balance	622,603	$ 111,651
Fair Value / Carrying Value	$ 622,603	$ 111,651
Weighted Average Cost of Funding (in Percent)	5.75%	3.34%
Weighted Average Term to Maturity (Months)	6 days	1 month 15 days
Agreements with mark-to-market collateral provisions | Securitized debt | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 622,603
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 non-mark-to-market collateral provisions | Estimate of Fair Value
Financing Agreements [Line Items]
Financing agreements, amortized cost	469,400	$ 578,900
Agreements with non-mark-to-market collateral provisions | Estimate of 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	1,217,671	1,004,260
Fair Value / Carrying Value	$ 1,216,697	$ 1,003,604
Weighted Average Cost of Funding (in Percent)	7.71%	5.00%
Weighted Average Term to Maturity (Months)	20 months 18 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	$ 469,400
Agreements with non-mark-to-market collateral provisions | Residential Whole Loans and REO | 0-3 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	36,341
Agreements with non-mark-to-market collateral provisions | Residential Whole Loans and REO | 3-6 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	10,151
Agreements with non-mark-to-market collateral provisions | Residential Whole Loans and REO | 6-12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	44,342
Agreements with non-mark-to-market collateral provisions | Residential Whole Loans and REO | Greater than 12 Months
Financing Agreements [Line Items]
Unpaid Principal Balance	$ 1,126,837
Securitized debt | Estimate of Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value		$ 2,400,000
Weighted Average Cost of Funding (in Percent)	(1.36%)	(0.14%)
Financing agreements, amortized cost	$ 4,100,000	$ 2,600,000
Securitized debt | Residential Whole Loans and REO
Financing Agreements [Line Items]
Unpaid Principal Balance	4,894,746	3,586,397
Fair Value / Carrying Value	$ 4,750,805	$ 3,357,590
Weighted Average Cost of Funding (in Percent)	4.00%	2.99%
Securitized debt | Residential Whole Loans and REO | Held At Fair Value
Financing Agreements [Line Items]
Fair Value / Carrying Value	$ 4,000,000
Convertible senior notes | Unsecured Debt
Financing Agreements [Line Items]
Unpaid Principal Balance	209,589	$ 229,989
Fair Value / Carrying Value	$ 208,989	$ 227,845
Weighted Average Cost of Funding (in Percent)	6.94%	6.94%
Weighted Average Term to Maturity (Months)	5 months 15 days	17 months 15 days
Impact of net Swap carry | Unsecured Debt
Financing Agreements [Line Items]
Weighted Average Cost of Funding (in Percent)	(1.36%)	(0.14%)