Debt Obligations - Schedule of Credit and Repurchase Facilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Debt Obligations
Debt Carrying Value	$ 4,967,952	$ 5,149,651
Collateral Carrying Value	$ 6,905,211	7,170,756
Wtd. Avg. Note Rate	6.07%
Outstanding principal balance repaid	$ 6,000	26,500
Notes payable - real estate owned	253,189	222,965
Mortgages
Debt Obligations
Notes payable - real estate owned	$ 253,200	$ 223,000
BTR CLO 1
Debt Obligations
Wtd. Avg. Note Rate	6.22%	6.29%
Investment grade notes retained	$ 41,000	$ 41,000
Structured Business
Debt Obligations
Debt Carrying Value	4,543,087	4,759,255
Collateral Carrying Value	$ 6,463,033	6,765,147
Wtd. Avg. Note Rate	6.15%
Deferred financing fees	$ 9,600	11,700
Structured Business \| $1.4B joint repurchase facility
Debt Obligations
Maximum borrowing capacity	1,400,000
Debt Carrying Value	1,031,189	882,635
Collateral Carrying Value	$ 1,569,762	1,468,161
Wtd. Avg. Note Rate	6.36%
Structured Business \| $1.22B repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 1,220,000
Debt Carrying Value	1,175,995	1,149,944
Collateral Carrying Value	$ 1,633,307	1,555,403
Wtd. Avg. Note Rate	5.66%
Structured Business \| $1B repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 1,000,000
Debt Carrying Value	774,998	879,499
Collateral Carrying Value	$ 1,082,767	1,207,513
Wtd. Avg. Note Rate	6.47%
Expiration period after the lender provides written notice	6 months
Line of credit facility, repurchase period	6 months
Structured Business \| $850M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 850,000
Debt Carrying Value	356,589	443,880
Collateral Carrying Value	$ 624,309	725,309
Wtd. Avg. Note Rate	6.50%
Structured Business \| $650M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 650,000
Debt Carrying Value	381,913	462,694
Collateral Carrying Value	$ 456,439	549,069
Wtd. Avg. Note Rate	6.19%
Structured Business \| $400M credit facility
Debt Obligations
Maximum borrowing capacity	$ 400,000
Debt Carrying Value	59,399	66,479
Collateral Carrying Value	$ 117,164	125,099
Wtd. Avg. Note Rate	7.01%
Structured Business \| $400M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 400,000
Debt Carrying Value	279,679	291,342
Collateral Carrying Value	$ 379,619	383,195
Wtd. Avg. Note Rate	5.98%
Structured Business \| $350M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 350,000
Debt Carrying Value	124,215	127,199
Collateral Carrying Value	$ 217,645	238,422
Wtd. Avg. Note Rate	5.73%
Structured Business \| $300M credit facility
Debt Obligations
Maximum borrowing capacity	$ 300,000
Debt Carrying Value	7,551	0
Collateral Carrying Value	$ 9,476	0
Wtd. Avg. Note Rate	6.76%
Structured Business \| $250M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 250,000
Debt Carrying Value	85,803	73,052
Collateral Carrying Value	$ 132,070	113,121
Wtd. Avg. Note Rate	6.79%
Structured Business \| $250M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 250,000
Debt Carrying Value	0	98,186
Collateral Carrying Value	$ 0	126,340
Wtd. Avg. Note Rate	0.00%
Structured Business \| $250M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 250,000
Debt Carrying Value	95,417	78,963
Collateral Carrying Value	$ 124,588	102,758
Wtd. Avg. Note Rate	6.25%
Structured Business \| $200M credit facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	48,665	41,114
Collateral Carrying Value	$ 65,277	59,147
Wtd. Avg. Note Rate	6.30%
Structured Business \| $22M loan specific credit facility
Debt Obligations
Maximum borrowing capacity	$ 22,000
Debt Carrying Value	20,792	63,456
Collateral Carrying Value	$ 26,000	87,000
Wtd. Avg. Note Rate	5.84%
Structured Business \| $40M credit facility
Debt Obligations
Maximum borrowing capacity	$ 40,000
Debt Carrying Value	15,570	15,532
Collateral Carrying Value	$ 24,610	24,610
Wtd. Avg. Note Rate	6.10%
Structured Business \| $35M working capital facility
Debt Obligations
Maximum borrowing capacity	$ 35,000
Debt Carrying Value	35,000	35,000
Collateral Carrying Value	$ 0	0
Wtd. Avg. Note Rate	6.66%
Structured Business \| Repurchase facility - securities
Debt Obligations
Debt Carrying Value	$ 50,312	50,280
Collateral Carrying Value	$ 0	0
Wtd. Avg. Note Rate	5.09%
Agency Business
Debt Obligations
Debt Carrying Value	$ 424,865	390,396
Collateral Carrying Value	$ 442,178	405,609
Wtd. Avg. Note Rate	5.24%
Deferred financing fees	$ 300	300
Agency Business \| $750M ASAP agreement
Debt Obligations
Maximum borrowing capacity	750,000
Debt Carrying Value	253,768	91,965
Collateral Carrying Value	$ 257,537	92,733
Wtd. Avg. Note Rate	4.88%
Agency Business \| $500M repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 500,000
Debt Carrying Value	23,169	89,427
Collateral Carrying Value	$ 23,573	89,573
Wtd. Avg. Note Rate	5.16%
Agency Business \| $200M credit facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	62,162	101,802
Collateral Carrying Value	$ 62,568	102,409
Wtd. Avg. Note Rate	5.37%
Agency Business \| $200M credit facility
Debt Obligations
Maximum borrowing capacity	$ 200,000
Debt Carrying Value	20,549	42,887
Collateral Carrying Value	$ 20,738	43,096
Wtd. Avg. Note Rate	6.07%
Agency Business \| $100M joint repurchase facility
Debt Obligations
Maximum borrowing capacity	$ 100,000
Debt Carrying Value	65,217	64,315
Collateral Carrying Value	$ 77,762	$ 77,798
Wtd. Avg. Note Rate	6.27%

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