Concentration of Credit Risk - Schedule of Loans Held for Investment Portfolio by Property Type (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Concentration Risk [Line Items]
Loan commitment	$ 3,899,345	$ 3,412,016
Unfunded commitment	$ 116,428	$ 127,866
% of loan commitment	100.00%	100.00%
Total unpaid principal balance	$ 3,783,609	$ 3,284,510
% of loan UPB	100.00%	100.00%
Multifamily
Concentration Risk [Line Items]
Loan commitment	$ 2,120,401	$ 1,777,221
Unfunded commitment	$ 60,246	$ 56,101
% of loan commitment	54.50%	52.00%
Total unpaid principal balance	$ 2,060,847	$ 1,721,480
% of loan UPB	54.50%	52.40%
Office
Concentration Risk [Line Items]
Loan commitment	$ 584,547	$ 606,047
Unfunded commitment	$ 17,810	$ 23,788
% of loan commitment	15.00%	17.80%
Total unpaid principal balance	$ 566,737	$ 582,259
% of loan UPB	15.00%	17.70%
Industrial
Concentration Risk [Line Items]
Loan commitment	$ 352,169	$ 166,000
Unfunded commitment	$ 21,946	$ 16,400
% of loan commitment	9.00%	4.90%
Total unpaid principal balance	$ 330,223	$ 149,600
% of loan UPB	8.70%	4.60%
Hotel
Concentration Risk [Line Items]
Loan commitment	$ 348,400	$ 348,400
Unfunded commitment	$ 9,575	$ 14,110
% of loan commitment	8.90%	10.20%
Total unpaid principal balance	$ 338,825	$ 334,290
% of loan UPB	9.00%	10.20%
Life Science
Concentration Risk [Line Items]
Loan commitment	$ 348,053	$ 368,573
Unfunded commitment	$ 4,576	$ 14,019
% of loan commitment	8.90%	10.80%
Total unpaid principal balance	$ 343,477	$ 354,554
% of loan UPB	9.00%	10.80%
Mixed-Use
Concentration Risk [Line Items]
Loan commitment	$ 78,775	$ 78,775
Unfunded commitment	$ 2,275	$ 3,448
% of loan commitment	2.00%	2.30%
Total unpaid principal balance	$ 76,500	$ 75,327
% of loan UPB	2.00%	2.30%
Self Storage
Concentration Risk [Line Items]
Loan commitment	$ 67,000	$ 67,000
Unfunded commitment	$ 0	$ 0
% of loan commitment	1.70%	2.00%
Total unpaid principal balance	$ 67,000	$ 67,000
% of loan UPB	1.80%	2.00%