Fair Value Measurements - Schedule of Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Financial assets
Total unpaid principal balance	$ 4,934,450	$ 4,118,050
Financial liabilities
Principal balance	4,198,054
Collateralized loan obligations
Financial liabilities
Principal balance	1,919,500	2,595,316
Secured credit agreements
Financial liabilities
Principal balance	1,522,156	591,245
Asset-specific financing arrangements
Financial liabilities
Principal balance	31,125	60,235
Secured revolving credit facility
Financial liabilities
Principal balance	264,963	31,466
Mortgage loans payable
Financial liabilities
Principal balance	60,310	31,200
Term Loan B
Financial liabilities
Principal balance	400,000
Carrying value
Financial assets
Fair value of financial assets	4,842,420	4,028,519
Carrying value \| Collateralized loan obligations
Financial liabilities
Fair value of financial liabilities	1,907,145	2,579,920
Carrying value \| Secured credit agreements
Financial liabilities
Fair value of financial liabilities	1,519,157	589,648
Carrying value \| Asset-specific financing arrangements
Financial liabilities
Fair value of financial liabilities	30,743	59,780
Carrying value \| Secured revolving credit facility
Financial liabilities
Fair value of financial liabilities	263,246	28,822
Carrying value \| Mortgage loans payable
Financial liabilities
Fair value of financial liabilities	59,950	30,838
Carrying value \| Term Loan B
Financial liabilities
Fair value of financial liabilities	393,268
Fair value \| Level I
Financial assets
Fair value of financial assets	0	0
Fair value \| Level I \| Collateralized loan obligations
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level I \| Secured credit agreements
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level I \| Asset-specific financing arrangements
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level I \| Secured revolving credit facility
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level I \| Mortgage loans payable
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level I \| Term Loan B
Financial liabilities
Fair value of financial liabilities	0
Fair value \| Level II
Financial assets
Fair value of financial assets	0	0
Fair value \| Level II \| Collateralized loan obligations
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level II \| Secured credit agreements
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level II \| Asset-specific financing arrangements
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level II \| Secured revolving credit facility
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level II \| Mortgage loans payable
Financial liabilities
Fair value of financial liabilities	0	0
Fair value \| Level II \| Term Loan B
Financial liabilities
Fair value of financial liabilities	400,000
Fair value \| Level III
Financial assets
Fair value of financial assets	4,915,290	4,083,758
Fair value \| Level III \| Collateralized loan obligations
Financial liabilities
Fair value of financial liabilities	1,910,307	2,579,151
Fair value \| Level III \| Secured credit agreements
Financial liabilities
Fair value of financial liabilities	1,520,432	590,653
Fair value \| Level III \| Asset-specific financing arrangements
Financial liabilities
Fair value of financial liabilities	31,125	60,127
Fair value \| Level III \| Secured revolving credit facility
Financial liabilities
Fair value of financial liabilities	264,963	31,466
Fair value \| Level III \| Mortgage loans payable
Financial liabilities
Fair value of financial liabilities	60,310	$ 31,200
Fair value \| Level III \| Term Loan B
Financial liabilities
Fair value of financial liabilities	$ 0