Variable Interest Entities - Narrative (Details)	3 Months Ended
	Mar. 31, 2022 USD ($) collateralizedLoanObligation loans	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Variable interest entities
Number of CLOs | collateralizedLoanObligation	5
Number of SASBs | loans	1
Assets	$ 81,187,898,000	$ 83,850,397,000
Liabilities	74,278,245,000	77,201,590,000
Temporary equity	261,685,000	214,915,000	$ 0	$ 0
Investments in unconsolidated entities	$ 89,250,000	$ 90,097,000
CMBS JV
Variable interest entities
Ownership percentage	51.00%
Primary beneficiary
Variable interest entities
Assets	$ 75,400,000
Liabilities	30,800,000
Primary beneficiary | CMBS Venture Holdings
Variable interest entities
Assets	341,400,000
Liabilities	79,600,000
Primary beneficiary | SPT Dolphin
Variable interest entities
Assets	1,300,000,000
Liabilities	0
Primary beneficiary | Woodstar Feeder Fund, L.P.
Variable interest entities
Assets	400,000,000
Liabilities	0
Temporary equity	300,000,000
Not primary beneficiary
Variable interest entities
Maximum risk of loss related to VIEs, on fair value basis	21,900,000
Not primary beneficiary | Measurement Period Adjustments
Variable interest entities
Investments in unconsolidated entities	22,500,000
Not primary beneficiary | Securitization SPEs
Variable interest entities
Long term debt, gross	$ 4,800,000,000