Debt and Preferred Equity Investments - Rollforward of Total Allowance for Loan Loss Reserves (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Loan loss reserve activity
Balance at beginning of year		$ 13,213	$ 1,750	$ 5,750
Current period provision for loan loss		0	20,693	0
Write-offs charged against allowance		(6,583)	(37,033)	(4,000)
Balance at end of year	$ 13,213	6,630	13,213	1,750
Write-offs charged against allowance		$ 6,583	37,033	4,000
Number of financing receivables on non-accrual without allowance for loan loss | loan		1
Financing receivable on non-accrual without allowance		$ 225,400
Investments Sold In 2021
Loan loss reserve activity
Write-offs charged against allowance		0
Write-offs charged against allowance		0
Investments Sold In 2020
Loan loss reserve activity
Write-offs charged against allowance	(19,000)
Write-offs charged against allowance	19,000
Cumulative Effect, Period of Adoption, Adjustment
Loan loss reserve activity
Balance at beginning of year		$ 0	27,803	0
Balance at end of year	$ 0		$ 0	$ 27,803