Fair Values - Schedule of Details of Book Value, Face Amount, and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financial assets
Cash and cash equivalents	$ 373,876	$ 350,014
Cash and cash equivalents, fair value	373,876	350,014
Loans receivable, net, book value	21,976,910	23,210,076
Loan receivable, net, face amount	23,010,660	23,923,719
Loan receivable, net, fair value	21,872,283	23,015,737
Financial liabilities
Long-term debt, face amount	16,000,571
Loan participations sold, net, book value	100,442	337,179
Loan participations sold, net, Face Amount	100,580	337,721
Loan participations sold, net, fair value	100,098	333,745
Secured debt, net
Financial liabilities
Long-term debt	12,096,705	12,683,095
Long-term debt, face amount	12,110,576	12,697,058
Long-term debt, fair value	11,928,849	12,425,609
Securitized debt obligations, net
Financial liabilities
Long-term debt	2,327,774	2,505,417
Long-term debt, face amount	2,328,492	2,507,514
Long-term debt, fair value	2,153,456	2,323,441
Asset-specific debt, net
Financial liabilities
Long-term debt	1,120,760	1,000,210
Long-term debt, face amount	1,125,854	1,004,097
Long-term debt, fair value	1,112,516	992,357
Secured term loans, net
Financial liabilities
Long-term debt	2,095,199	2,101,632
Long-term debt, face amount	2,124,223	2,135,221
Long-term debt, fair value	2,055,445	2,102,950
Senior secured notes, net
Financial liabilities
Long-term debt	337,336	362,763
Long-term debt, face amount	339,918	366,090
Long-term debt, fair value	306,139	327,081
Convertible notes, net
Financial liabilities
Long-term debt	296,486	295,847
Long-term debt, face amount	300,000	300,000
Long-term debt, fair value	$ 272,061	$ 272,076