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Loans - Investments in Mortgages and Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Investments in loans
Carrying Value	$ 22,453,605	$ 21,627,097
Face Amount	22,809,676	21,922,738
Credit loss allowances:	(419,156)	(440,842)
Total net loans	$ 22,034,449	$ 21,186,255	$ 20,320,224	$ 17,953,021
Residential, fair value option
Investments in loans
Weighted Average Life (in years)	25 years 4 months 24 days	25 years 9 months 18 days
Commercial loans:
Investments in loans
Carrying Value	$ 17,144,591
Credit loss allowances:	(406,224)
Infrastructure first priority loans
Investments in loans
Carrying Value	2,864,012
Credit loss allowances:	(12,932)
Loans held for investment
Investments in loans
Carrying Value	20,236,124	$ 19,303,554
Face Amount	20,379,741	19,419,886
Credit loss allowances:	(419,156)	(440,842)
Loans held for investment \| Commercial loans:
Investments in loans
Carrying Value	17,144,591	16,464,698
Face Amount	17,225,133	16,529,513
Credit loss allowances:	(406,224)	(426,365)
Total net loans	16,738,367	16,038,333	14,765,064	12,895,064
Loans held for investment \| Infrastructure first priority loans
Investments in loans
Carrying Value	2,864,012	2,838,856
Face Amount	$ 2,918,632	$ 2,890,373
Weighted Average Life (in years)	5 years	5 years 1 month 6 days
Credit loss allowances:	$ (12,932)	$ (14,477)
Total net loans	$ 2,851,080	$ 2,824,379	3,060,322	2,541,949
Loans held for investment \| Weighted Average Coupon \| Infrastructure first priority loans
Investments in loans
Weighted Average Coupon	7.30%	7.40%
Loans held-for-sale
Investments in loans
Carrying Value	$ 2,217,481	$ 2,323,543
Face Amount	2,429,935	2,502,852
Credit loss allowances:	0
Total net loans	2,217,481	2,323,543	$ 2,494,838	$ 2,516,008
Loans held-for-sale \| Residential, fair value option
Investments in loans
Carrying Value	2,154,653	2,278,067
Face Amount	2,364,897	2,455,552
Loans held-for-sale \| Commercial, fair value option
Investments in loans
Carrying Value	62,828	45,476
Face Amount	$ 65,038	$ 47,300
Weighted Average Life (in years)	6 years 1 month 6 days	8 years 6 months
Loans held-for-sale \| Weighted Average Coupon \| Residential, fair value option
Investments in loans
Weighted Average Coupon	4.40%	4.40%
Loans held-for-sale \| Weighted Average Coupon \| Commercial, fair value option
Investments in loans
Weighted Average Coupon	6.20%	6.40%
First Mortgage \| Loans held for investment
Investments in loans
Carrying Value	$ 16,799,181	$ 16,086,585
Face Amount	$ 16,877,748	$ 16,148,916
Weighted Average Life (in years)	2 years 8 months 12 days	2 years 8 months 12 days
First Mortgage \| Loans held for investment \| Weighted Average Coupon
Investments in loans
Weighted Average Coupon	7.00%	7.00%
Subordinated Mortgages \| Loans held for investment
Investments in loans
Carrying Value	$ 4,925	$ 15,683
Face Amount	$ 4,925	$ 15,290
Weighted Average Life (in years)	0 years	1 month 6 days
Subordinated Mortgages \| Loans held for investment \| Weighted Average Coupon
Investments in loans
Weighted Average Coupon	0.00%	11.10%
Mezzanine Loans
Investments in loans
Total net loans	$ 1,400,000	$ 1,300,000
Mezzanine Loans \| Loans held for investment
Investments in loans
Carrying Value	289,855	311,175
Face Amount	$ 291,722	$ 313,619
Weighted Average Life (in years)	2 years 2 months 12 days	2 years 9 months 18 days
Mezzanine Loans \| Loans held for investment \| Weighted Average Coupon
Investments in loans
Weighted Average Coupon	10.40%	10.80%
Other \| Loans held for investment
Investments in loans
Carrying Value	$ 50,630	$ 51,255
Face Amount	$ 50,738	$ 51,688
Weighted Average Life (in years)	2 years 1 month 6 days	2 years 7 months 6 days
Other \| Loans held for investment \| Weighted Average Coupon
Investments in loans
Weighted Average Coupon	9.50%	9.10%
Residential loans, fair value option \| Loans held for investment
Investments in loans
Carrying Value	$ 227,521
Face Amount	$ 235,976
Residential loans, fair value option \| Loans held for investment \| Weighted Average Coupon
Investments in loans
Weighted Average Coupon	5.50%