Schedule IV - Reconciliation of Mortgage Loans on Real Estate (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Mortgage Loans On Real Estate [Abstract]
Balance at January 1,		$ 6,464,095	$ 6,163,159
Loan fundings		3,056,293	914,010
Payment in kind interest		88,024	103,847
Amortization of deferred fees and expenses		26,487	28,310
Collections of principal, including sales proceeds		(2,926,566)	(732,969)
Deferred origination fees and expenses		(39,361)	(6,262)
Realized loss on sale of investments		(141)	(640)	$ 103
Transfer to real estate owned, net		(103,901)
Provision for loan losses (1)	[1]	(62,785)	(6,000)
Balance at December 31,		$ 6,502,145	$ 6,464,095	$ 6,163,159

[1] See Note 3 – Loans Portfolio of the consolidated financial statements for information on loan loss allowances.