Loans Held-for-Investment, Net of Allowance for Credit Losses - Schedule of Loans Held-for-Investment by Internal Risk Rating (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($) loan	Dec. 31, 2025 USD ($) loan	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	40	43
Unpaid Principal Balance	$ 1,514,892	$ 1,689,967
Loans held-for-investment, net	1,362,799	1,537,732	$ 1,760,377	$ 1,897,648
Current year	0	0
Year one	0	0
Year two	0	54,844
Year three	55,991	322,831
Year four	256,894	412,741
Prior	1,049,914	747,316
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	(15,361)
Prior	0	(65,137)
Total	$ 0	$ (80,498)
Risk Rating 1
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	4	7
Unpaid Principal Balance	$ 106,541	$ 293,896
Loans held-for-investment, net	105,840	292,614
Current year	0	0
Year one	0	0
Year two	0	0
Year three	0	113,678
Year four	46,551	37,477
Prior	$ 59,289	$ 141,459
Risk Rating 2
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	6	8
Unpaid Principal Balance	$ 204,120	$ 268,935
Loans held-for-investment, net	202,684	265,628
Current year	0	0
Year one	0	0
Year two	0	0
Year three	0	113,940
Year four	68,342	151,688
Prior	$ 134,342	$ 0
Risk Rating 3
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	19	20
Unpaid Principal Balance	$ 674,457	$ 706,363
Loans held-for-investment, net	658,000	676,253
Current year	0	0
Year one	0	0
Year two	0	54,844
Year three	0	60,395
Year four	107,183	161,020
Prior	$ 550,817	$ 399,994
Risk Rating 4
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	6	4
Unpaid Principal Balance	$ 265,120	$ 172,086
Loans held-for-investment, net	240,960	159,618
Current year	0	0
Year one	0	0
Year two	0	0
Year three	55,991	0
Year four	0	62,556
Prior	$ 184,969	$ 97,062
Risk Rating 5
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| loan	5	4
Unpaid Principal Balance	$ 264,654	$ 248,687
Loans held-for-investment, net	155,315	143,619
Current year	0	0
Year one	0	0
Year two	0	0
Year three	0	34,818
Year four	34,818	0
Prior	$ 120,497	$ 108,801

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