Commercial Mortgage Loans, Subordinate Loans and Other Lending Assets, Net - Allocation of Carrying Value of Loan Portfolio Based on Internal Risk Ratings (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2024 USD ($) Loan	Dec. 31, 2023 USD ($) Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	50	50
Total	$ 8,329,221	$ 8,384,575
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	100.00%	100.00%
Year 1	$ 639,886	$ 440,720
Year 2	490,664	2,707,083
Year 3	2,581,807	2,285,902
Year 4	2,224,218	557,204
Year 5	421,975	1,597,927
Prior	1,970,671	795,739
General CECL Allowance	(35,319)	(26,482)
Carrying value, net	$ 8,293,902	$ 8,358,093
Weighted-Average Risk Rating	3	3
Gross write-offs	$ 0	$ 81,890
1
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	0	0
Total	$ 0	$ 0
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	0.00%	0.00%
Year 1	$ 0	$ 0
Year 2	0	0
Year 3	0	0
Year 4	0	0
Year 5	0	0
Prior	$ 0	$ 0
2
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	4	4
Total	$ 479,843	$ 478,440
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	5.80%	5.70%
Year 1	$ 0	$ 0
Year 2	0	280,572
Year 3	390,038	0
Year 4	24,471	0
Year 5	0	132,309
Prior	$ 65,334	$ 65,560
3
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	41	42
Total	$ 7,302,939	$ 7,548,252
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	87.70%	90.00%
Year 1	$ 639,886	$ 440,720
Year 2	490,664	2,426,511
Year 3	1,849,832	2,285,902
Year 4	2,199,747	387,323
Year 5	394,094	1,465,618
Prior	$ 1,728,716	$ 542,177
4
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	2	2
Total	$ 420,049	$ 88,112
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	5.00%	1.10%
Year 1	$ 0	$ 0
Year 2	0	0
Year 3	341,937	0
Year 4	0	0
Year 5	0	0
Prior	$ 78,112	$ 88,112
5
Financing Receivable, Credit Quality Indicator [Line Items]
Number of Loans \| Loan	3	2
Total	$ 126,390	$ 269,771
Mortgage loans on real estate, commercial and consumer, percentage of portfolio	1.50%	3.20%
Year 1	$ 0	$ 0
Year 2	0	0
Year 3	0	0
Year 4	0	169,881
Year 5	27,881	0
Prior	$ 98,509	$ 99,890

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