Variable Interest Entity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($) item	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Assets:
Restricted cash	$ 922,531		$ 486,690	$ 569,928		$ 197,470
Loans and investments, net	14,791,426		11,981,048
Other assets	346,912		269,946
Total assets	17,762,129		15,073,845
Liabilities:
Collateralized loan obligations	7,971,996		5,892,810
Other liabilities	303,948		287,885
Total liabilities	14,808,123		12,523,861
Loan loss reserves related to VIEs	122,296	$ 121,331	113,241	$ 131,534	$ 138,447	$ 148,329
Consolidated VIEs
Assets:
Total assets	9,754,533		7,144,806
Liabilities:
Total liabilities	7,989,263		5,902,623
Unconsolidated VIEs
Assets:
Total assets	$ 663,639
Liabilities:
Number of VIEs where the reporting entity is not VIE's primary beneficiary and VIEs have variable interest | item	30
Carrying amount of loans and investments before reserves related to VIEs	$ 127,900
Loan loss reserves related to VIEs	77,900
Exposure to real estate debt	4,330,000
Collateralized loan obligations | Consolidated VIEs
Assets:
Restricted cash	901,910		466,523
Loans and investments, net	8,789,844		6,616,809
Other assets	62,779		61,474
Total assets	9,754,533		7,144,806
Liabilities:
Collateralized loan obligations	7,971,996		5,892,810
Other liabilities	17,267		9,813
Total liabilities	7,989,263		$ 5,902,623
Loans | Unconsolidated VIEs
Assets:
Total assets	480,240
APL certificates | Unconsolidated VIEs
Assets:
Total assets	125,094
B Piece bonds | Unconsolidated VIEs
Assets:
Total assets	34,814
Equity investments | Unconsolidated VIEs
Assets:
Total assets	23,203
Agency interest only strips | Unconsolidated VIEs
Assets:
Total assets	$ 288