Variable interest entities and securitization activities - Securitized Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Variable interest entities
Current Principal Balance	$ 7,925,426	$ 6,898,073
Current principal balance of non-company sponsored securitized loans	700	1,600
Consolidated VIEs
Variable interest entities
Current Principal Balance	4,442,263	5,122,620
Carrying value	$ 4,406,517	$ 5,066,833
Weighted Average Rate	7.20%	6.90%
ReadyCap Lending Small Business Trust 2019-2
Variable interest entities
Current Principal Balance	$ 25,512	$ 32,175
Carrying value	$ 25,512	$ 32,175
Weighted Average Rate	8.00%	7.60%
ReadyCap Lending Small Business Trust 2023-3
Variable interest entities
Current Principal Balance	$ 114,485	$ 121,527
Carrying value	$ 112,549	$ 119,308
Weighted Average Rate	8.60%	8.50%
Sutherland Commercial Mortgage Trust 2017-SBC6
Variable interest entities
Current Principal Balance	$ 277	$ 1,550
Carrying value	$ 277	$ 1,532
Weighted Average Rate	5.00%	5.00%
Sutherland Commercial Mortgage Trust 2019-SBC8
Variable interest entities
Current Principal Balance	$ 97,659	$ 105,281
Carrying value	$ 96,256	$ 103,733
Weighted Average Rate	2.90%	2.90%
Sutherland Commercial Mortgage Trust 2021-SBC10
Variable interest entities
Current Principal Balance	$ 69,979	$ 81,214
Carrying value	$ 68,902	$ 79,952
Weighted Average Rate	1.60%	1.60%
ReadyCap Commercial Mortgage Trust 2015-2
Variable interest entities
Current Principal Balance	$ 1,758	$ 1,902
Carrying value	$ 1,688	$ 1,753
Weighted Average Rate	5.10%	5.10%
ReadyCap Commercial Mortgage Trust 2016-3
Variable interest entities
Current Principal Balance	$ 8,901	$ 9,038
Carrying value	$ 8,670	$ 8,723
Weighted Average Rate	5.30%	5.20%
ReadyCap Commercial Mortgage Trust 2018-4
Variable interest entities
Current Principal Balance	$ 52,078	$ 53,052
Carrying value	$ 50,569	$ 51,309
Weighted Average Rate	4.60%	4.50%
ReadyCap Commercial Mortgage Trust 2019-5
Variable interest entities
Current Principal Balance	$ 84,579	$ 88,520
Carrying value	$ 80,128	$ 83,529
Weighted Average Rate	4.90%	4.70%
ReadyCap Commercial Mortgage Trust 2019-6
Variable interest entities
Current Principal Balance	$ 192,110	$ 199,379
Carrying value	$ 188,680	$ 195,496
Weighted Average Rate	3.40%	3.40%
ReadyCap Commercial Mortgage Trust 2022-7
Variable interest entities
Current Principal Balance	$ 194,429	$ 195,866
Carrying value	$ 188,188	$ 188,995
Weighted Average Rate	4.20%	4.20%
Ready Capital Mortgage Financing 2021-FL5
Variable interest entities
Current Principal Balance	$ 113,339	$ 273,681
Carrying value	$ 113,339	$ 273,623
Weighted Average Rate	7.40%	6.60%
Ready Capital Mortgage Financing 2021-FL6
Variable interest entities
Current Principal Balance	$ 242,920	$ 417,782
Carrying value	$ 242,920	$ 416,467
Weighted Average Rate	6.90%	6.40%
Ready Capital Mortgage Financing 2021-FL7
Variable interest entities
Current Principal Balance	$ 552,629	$ 586,117
Carrying value	$ 552,131	$ 583,771
Weighted Average Rate	7.10%	6.70%
Ready Capital Mortgage Financing 2022-FL8
Variable interest entities
Current Principal Balance	$ 789,968	$ 808,671
Carrying value	$ 788,547	$ 805,220
Weighted Average Rate	7.50%	7.00%
Ready Capital Mortgage Financing 2022-FL9
Variable interest entities
Current Principal Balance	$ 453,978	$ 511,622
Carrying value	$ 451,260	$ 505,917
Weighted Average Rate	8.50%	8.10%
Ready Capital Mortgage Financing 2022-FL10
Variable interest entities
Current Principal Balance	$ 577,204	$ 654,116
Carrying value	$ 572,469	$ 646,141
Weighted Average Rate	8.20%	7.80%
Ready Capital Mortgage Financing 2023-FL11
Variable interest entities
Current Principal Balance	$ 429,849	$ 473,481
Carrying value	$ 427,051	$ 468,307
Weighted Average Rate	8.20%	8.20%
Ready Capital Mortgage Financing 2023-FL12
Variable interest entities
Current Principal Balance	$ 440,609	$ 507,646
Carrying value	$ 437,381	$ 500,882
Weighted Average Rate	8.10%	8.00%