Secured Borrowings - Collateralized Loan Obligations (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2025 USD ($) security	Dec. 31, 2024 USD ($) security	Oct. 31, 2024 USD ($)	May 31, 2024 USD ($)	Feb. 28, 2022 USD ($)	Jan. 31, 2022 USD ($)	May 31, 2021 USD ($)	Aug. 31, 2019 USD ($)
Summary of CLO
Carrying Value	$ 3,165,296	$ 3,196,426
Collateral assets
Summary of CLO
Face Amount	3,835,698	3,980,769
Carrying Value	4,055,890	4,076,969
Financing
Summary of CLO
Face Amount	3,172,013	3,204,296
Carrying Value	$ 3,165,296	$ 3,196,426
STWD 2022-FL3
Summary of CLO
Face Amount					$ 1,000,000
STWD 2022-FL3 | Collateral assets
Summary of CLO
Count | security	33	35
Face Amount	$ 916,341	$ 921,139
Carrying Value	$ 920,294	$ 927,656
Weighted Average Spread	2.99%	3.32%
STWD 2022-FL3 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 756,961	$ 764,223
Carrying Value	$ 756,256	$ 762,992
Weighted Average Spread	1.95%	1.94%
STWD 2021-HTS | Collateral assets
Summary of CLO
Count | security	1	1
Face Amount	$ 159,013	$ 174,417
Carrying Value	$ 159,844	$ 175,338
Weighted Average Spread	3.97%	4.01%
STWD 2021-HTS | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 139,104	$ 154,508
Carrying Value	$ 139,104	$ 154,508
Weighted Average Spread	2.98%	2.81%
STWD 2021-FL2
Summary of CLO
Face Amount							$ 1,300,000
STWD 2021-FL2 | Collateral assets
Summary of CLO
Count | security	21	22
Face Amount	$ 992,433	$ 1,047,685
Carrying Value	$ 1,043,555	$ 1,053,503
Weighted Average Spread	3.27%	3.64%
STWD 2021-FL2 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 819,633	$ 829,137
Carrying Value	$ 819,633	$ 829,137
Weighted Average Spread	1.69%	1.68%
STWD 2019-FL1
Summary of CLO
Face Amount								$ 1,100,000
STWD 2019-FL1 | Collateral assets
Summary of CLO
Count | security	7	7
Face Amount	$ 383,740	$ 383,853
Carrying Value	$ 385,898	$ 385,712
Weighted Average Spread	3.42%	3.50%
STWD 2019-FL1 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 220,115	$ 220,228
Carrying Value	$ 220,115	$ 220,228
Weighted Average Spread	2.10%	2.10%
Starwood 2024-SIF4
Summary of CLO
Face Amount			$ 600,000
Starwood 2024-SIF4 | Collateral assets
Summary of CLO
Count | security	30	33
Face Amount	$ 581,763	$ 558,707
Carrying Value	$ 623,028	$ 609,072
Weighted Average Spread	3.95%	3.95%
Starwood 2024-SIF4 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 496,200	$ 496,200
Carrying Value	$ 493,152	$ 492,936
Weighted Average Spread	2.10%	2.10%
STWD 2024-SIF3
Summary of CLO
Face Amount				$ 400,000
STWD 2024-SIF3 | Collateral assets
Summary of CLO
Count | security	30	31
Face Amount	$ 395,865	$ 394,070
Carrying Value	$ 408,778	$ 410,263
Weighted Average Spread	3.98%	4.01%
STWD 2024-SIF3 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 330,000	$ 330,000
Carrying Value	$ 327,737	$ 327,553
Weighted Average Spread	2.41%	2.41%
STWD 2021-SIF2
Summary of CLO
Face Amount						$ 500,000
STWD 2021-SIF2 | Collateral assets
Summary of CLO
Count | security	27	30
Face Amount	$ 406,543	$ 500,898
Carrying Value	$ 514,493	$ 515,425
Weighted Average Spread	3.83%	3.79%
STWD 2021-SIF2 | Financing
Summary of CLO
Count | security	1	1
Face Amount	$ 410,000	$ 410,000
Carrying Value	$ 409,299	$ 409,072
Weighted Average Spread	2.11%	2.11%