Commercial Loans - Components of the carrying value of the commercial real estate loans (Details) - USD ($) $ in Thousands		1 Months Ended
	Sep. 15, 2021	Mar. 31, 2019	Dec. 31, 2021	Dec. 31, 2020
Commercial Loans, at Fair Value
Variable Interest Entity [Line Items]
Principal balance			$ 177,797	$ 256,694
Unamortized premium			0	0
Unamortized discount			0	(53)
Amortized cost			177,797	256,641
Gross unrealized gains			0	1
Gross unrealized losses			(61,587)	(14,585)
Fair Value			116,210	242,057
CSMC Trust | Securitized Commercial Loans
Variable Interest Entity [Line Items]
Principal balance			1,400,000
RETL Trust Securitized Commercial Loan, at Fair Value (1)
Variable Interest Entity [Line Items]
Principal balance			0	354,202
Unamortized premium			0	180
Unamortized discount			0	0
Amortized cost			0	354,382
Gross unrealized gains			0	0
Gross unrealized losses			0	(14,998)
Fair Value			0	339,384
RETL Trust Securitized Commercial Loan, at Fair Value (1) | Securitized Commercial Loans
Variable Interest Entity [Line Items]
Variable interest entity, amount acquired, eligible risk retention	$ 45,300	$ 45,300
CSMC USA Trust Securitized Commercial Loan, at Fair Value
Variable Interest Entity [Line Items]
Principal balance			1,385,591	1,385,591
Unamortized premium			0	0
Unamortized discount			(110,770)	(135,653)
Amortized cost			1,274,821	1,249,938
Gross unrealized gains			80,987	16,013
Gross unrealized losses			0	0
Fair Value			1,355,808	1,265,951
RSBC Trust Commercial Loans, at Fair Value
Variable Interest Entity [Line Items]
Principal balance			14,362	68,750
Unamortized premium			0	0
Unamortized discount			0	(94)
Amortized cost			14,362	68,656
Gross unrealized gains			0	0
Gross unrealized losses			0	(190)
Fair Value			$ 14,362	$ 68,466