Loans Held for Investment, net - Loan Risk Ratings Carrying Value (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2026 USD ($) loan	Dec. 31, 2025 USD ($) loan
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	26	24
Percentage of Portfolio	100.00%	100.00%
Year one	$ 251,299	$ 148,568
Year two	154,580	196,740
Year three	136,692	54,161
Year four	0	65,510
Years five	65,490	194,088
Prior	95,704	26,640
Accrued interest receivable	$ 703,765	$ 685,707
1
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	0	3
Percentage of Portfolio	0.00%	16.00%
Year one	$ 0	$ 0
Year two	0	57,599
Year three	0	0
Year four	0	0
Years five	0	54,982
Prior	0	0
Accrued interest receivable	$ 0	$ 112,581
2
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	2	2
Percentage of Portfolio	9.00%	8.00%
Year one	$ 0	$ 27,992
Year two	63,601	0
Year three	0	28,988
Year four	0	0
Years five	0	0
Prior	0	0
Accrued interest receivable	$ 63,601	$ 56,980
3
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	18	15
Percentage of Portfolio	68.00%	59.00%
Year one	$ 251,299	$ 120,576
Year two	90,979	139,141
Year three	136,692	25,173
Year four	0	65,510
Years five	0	23,593
Prior	0	26,640
Accrued interest receivable	$ 478,970	$ 400,633
4
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	5	4
Percentage of Portfolio	19.00%	17.00%
Year one	$ 0	$ 0
Year two	0	0
Year three	0	0
Year four	0	0
Years five	65,490	115,513
Prior	71,030	0
Accrued interest receivable	$ 136,520	$ 115,513
5
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of Loans \| loan	1	0
Percentage of Portfolio	4.00%	0.00%
Year one	$ 0	$ 0
Year two	0	0
Year three	0	0
Year four	0	0
Years five	0	0
Prior	24,674	0
Accrued interest receivable	$ 24,674	$ 0

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