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Debt Obligations - Credit and Repurchase Facilities (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023	Apr. 30, 2024	Mar. 31, 2024	Feb. 29, 2024
Debt Obligations
Debt Carrying Value	$ 3,160,384	$ 3,237,827
Collateral Carrying Value	$ 4,509,926	4,606,657
Wtd. Avg. Note Rate	7.83%
Outstanding principal balance repaid	$ 36,700	43,100
Structured Business
Debt Obligations
Debt Carrying Value	2,825,213	2,824,501
Collateral Carrying Value	$ 4,168,998	4,062,162
Wtd. Avg. Note Rate	7.96%
Deferred financing fees	$ 6,500	4,800
Structured Business \| $1.9B joint repurchase facility
Debt Obligations
Maximum borrowing capacity	1,900,000
Debt Carrying Value	668,522	868,077
Collateral Carrying Value	$ 1,097,067	1,371,436
Wtd. Avg. Note Rate	7.85%
Structured Business \| $1B repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 1,000,000
Debt Carrying Value	291,605	385,779
Collateral Carrying Value	$ 465,061	589,533
Wtd. Avg. Note Rate	7.83%
Structured Business \| $1B repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 1,000,000			$ 1,000,000
Debt Carrying Value	668,484	447,490
Collateral Carrying Value	$ 912,135	597,205
Wtd. Avg. Note Rate	8.29%
Expiration period after the lender provides written notice	6 months
Line of credit facility, repurchase period	6 months
Structured Business \| $649M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 649,000
Debt Carrying Value	454,926	355,328
Collateral Carrying Value	$ 620,340	506,753
Wtd. Avg. Note Rate	7.81%
Structured Business \| $350M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 350,000			$ 350,000
Debt Carrying Value	151,611	262,820
Collateral Carrying Value	$ 228,535	362,465
Wtd. Avg. Note Rate	7.53%
Length of extension option				1 year
Structured Business \| $250M credit facility
Debt Obligations
Maximum borrowing capacity	$ 250,000			$ 250,000
Debt Carrying Value	112,647	0
Collateral Carrying Value	$ 217,110	0
Wtd. Avg. Note Rate	8.70%
Length of extension option				1 year
Structured Business \| $250M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 250,000
Debt Carrying Value	13,922	17,964
Collateral Carrying Value	$ 23,088	23,088
Wtd. Avg. Note Rate	7.30%
Structured Business \| $250M credit facility
Debt Obligations
Maximum borrowing capacity	$ 250,000
Debt Carrying Value	0	0
Collateral Carrying Value	$ 0	0
Wtd. Avg. Note Rate	0.00%
Structured Business \| $200M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	92,144	45,969
Collateral Carrying Value	$ 133,503	68,762
Wtd. Avg. Note Rate	7.99%
Structured Business \| $200M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	73,338	107,324
Collateral Carrying Value	$ 95,568	141,130
Wtd. Avg. Note Rate	7.35%
Structured Business \| $166M loan specific credit facilities
Debt Obligations
Maximum borrowing capacity	$ 166,000
Debt Carrying Value	138,010	120,328
Collateral Carrying Value	$ 188,562	161,700
Wtd. Avg. Note Rate	7.16%
Structured Business \| $150M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 150,000
Debt Carrying Value	112,076	120,610
Collateral Carrying Value	$ 149,727	162,068
Wtd. Avg. Note Rate	8.45%
Structured Business \| $100M credit facility
Debt Obligations
Maximum borrowing capacity	$ 100,000		$ 100,000
Debt Carrying Value	6,775	32,579
Collateral Carrying Value	$ 13,692	41,522
Wtd. Avg. Note Rate	7.13%
Structured Business \| $50M credit facility
Debt Obligations
Maximum borrowing capacity	$ 50,000
Debt Carrying Value	0	29,200
Collateral Carrying Value	$ 0	36,500
Wtd. Avg. Note Rate	0.00%
Structured Business \| $40M credit facility
Debt Obligations
Maximum borrowing capacity	$ 40,000
Debt Carrying Value	15,518	0
Collateral Carrying Value	$ 24,610	0
Wtd. Avg. Note Rate	7.79%
Structured Business \| $35M working capital facility
Debt Obligations
Maximum borrowing capacity	$ 35,000
Debt Carrying Value	0	0
Collateral Carrying Value	$ 0	0
Wtd. Avg. Note Rate	0.00%
Structured Business \| Repurchase facility - securities
Debt Obligations
Debt Carrying Value	$ 25,635	31,033
Collateral Carrying Value	$ 0	0
Wtd. Avg. Note Rate	7.13%
Structured Business \| $500M repurchase facility
Debt Obligations
Maximum borrowing capacity					$ 500,000
Structured Business \| $200M credit facility
Debt Obligations
Maximum borrowing capacity				$ 200,000
Agency Business
Debt Obligations
Debt Carrying Value	$ 335,171	413,326
Collateral Carrying Value	$ 340,928	544,495
Wtd. Avg. Note Rate	6.76%
Deferred financing fees	$ 200	300
Agency Business \| $100M credit facility
Debt Obligations
Maximum borrowing capacity	100,000
Debt Carrying Value	30,005	0
Collateral Carrying Value	$ 30,010	0
Wtd. Avg. Note Rate	6.79%
Agency Business \| $50M credit facility
Debt Obligations
Maximum borrowing capacity	$ 50,000
Debt Carrying Value	6,165	29,083
Collateral Carrying Value	$ 6,166	29,418
Wtd. Avg. Note Rate	6.68%
Agency Business \| $750M ASAP agreement
Debt Obligations
Maximum borrowing capacity	$ 750,000
Debt Carrying Value	53,516	73,011
Collateral Carrying Value	$ 54,095	73,781
Wtd. Avg. Note Rate	6.48%
Agency Business \| $500M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 500,000
Debt Carrying Value	140,797	115,730
Collateral Carrying Value	$ 141,410	241,895
Wtd. Avg. Note Rate	6.82%
Agency Business \| $200M credit facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	96,237	187,138
Collateral Carrying Value	$ 97,064	187,185
Wtd. Avg. Note Rate	6.73%
Agency Business \| $100M joint repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 100,000
Debt Carrying Value	7,920	7,833
Collateral Carrying Value	$ 11,345	11,350
Wtd. Avg. Note Rate	7.74%
Agency Business \| $1M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 1,000
Debt Carrying Value	531	531
Collateral Carrying Value	$ 838	$ 866
Wtd. Avg. Note Rate	7.80%
Structured and Agency Business \| $3 Billion joint repurchase facility
Debt Obligations
Maximum borrowing capacity					$ 3,000,000
Structured and Agency Business \| $2 Billion joint repurchase facility
Debt Obligations
Maximum borrowing capacity				$ 2,000,000