Loans - Risk Ratings by Class of Loan (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Investments in loans
Total Amortized Cost Basis	$ 19,396,682	$ 18,401,316
Credit Loss Allowance	428,067	448,295
Loans held-for-sale
Investments in loans
Total Amortized Cost Basis	2,446,636	$ 2,516,008
Credit Loss Allowance	0
Commercial loans:
Investments in loans
2025	888,082
2024	911,797
2023	947,622
2022	3,486,616
2021	5,626,376
Prior	2,368,229
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	14,228,722
Credit Loss Allowance	415,675
Commercial loans: \| LTV less than 60%
Investments in loans
2025	481,260
2024	298,146
2023	418,786
2022	2,010,833
2021	1,929,993
Prior	648,161
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	5,787,179
Credit Loss Allowance	15,329
Commercial loans: \| LTV 60% - 70%
Investments in loans
2025	294,009
2024	259,716
2023	458,912
2022	1,170,652
2021	2,565,067
Prior	384,394
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	5,132,750
Credit Loss Allowance	105,844
Commercial loans: \| LTV > 70%
Investments in loans
2025	112,813
2024	353,935
2023	65,374
2022	263,263
2021	1,131,316
Prior	1,330,749
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	3,257,450
Credit Loss Allowance	289,577
Commercial loans: \| Credit deteriorated
Investments in loans
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	4,925
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	4,925
Credit Loss Allowance	4,925
Commercial loans: \| Defeased and other
Investments in loans
2025	0
2024	0
2023	4,550
2022	41,868
2021	0
Prior	0
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	46,418
Credit Loss Allowance	0
Infrastructure loans:
Investments in loans
2025	529,581
2024	942,716
2023	705,234
2022	57,586
2021	120,398
Prior	364,708
Revolving Loans Amortized Cost Total	1,101
Total Amortized Cost Basis	2,721,324
Credit Loss Allowance	12,392
Infrastructure loans: \| Power
Investments in loans
2025	263,660
2024	609,908
2023	292,682
2022	0
2021	28,651
Prior	276,553
Revolving Loans Amortized Cost Total	1,101
Total Amortized Cost Basis	1,472,555
Credit Loss Allowance	5,094
Infrastructure loans: \| Oil and gas
Investments in loans
2025	265,921
2024	332,808
2023	412,552
2022	57,586
2021	91,747
Prior	88,155
Revolving Loans Amortized Cost Total	0
Total Amortized Cost Basis	1,248,769
Credit Loss Allowance	$ 7,298

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