Other Assets and Liabilities - Summary of Components of Other Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Other Assets And Liabilities Disclosure [Abstract]
Secured debt repayments pending servicer remittance	$ 105,078	$ 13,526
Accrued dividends payable	81,306	107,390	$ 106,824
Accrued interest payable	74,168	97,820
Derivative liabilities	50,256	94,817
Accrued management and incentive fees payable	18,605	26,342
Current expected credit loss reserves for unfunded loan commitments	8,307	15,371	$ 13,600
Accounts payable and other liabilities	8,662	7,265
Other liabilities	$ 346,382	$ 362,531