Mortgage Notes Receivable - Allowance for loan loss (Details) - USD ($) $ in Thousands		3 Months Ended
		Jun. 30, 2022		Mar. 31, 2022		Jun. 30, 2021	Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Credit Loss, Beginning Balance		$ 8,647		$ 10,394	[1]	$ 10,663	$ 10,590
Adoption of ASU 2016-13		9,526	[2]	8,647		10,943	10,663
Provision for loan losses (benefits)		2,381		1,554		280	1,761
Charge offs				(3,301)	[3]	(1,502)	(1,688)	[3]
Allowance for Credit Loss, Ending Balance		9,526	[2]	8,647		10,943	10,663
Unfunded Loan Commitment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Credit Loss, Beginning Balance	[4]	1,097		904		947	0
Adoption of ASU 2016-13		1,410		1,097	[4]	725	947	[4]
Provision for loan losses (benefits)		313		193	[4]	(222)	947	[4]
Charge offs						0	0	[3],[4]
Allowance for Credit Loss, Ending Balance		1,410		1,097	[4]	725	947	[4]
Funded And Unfunded Loan Commitment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Credit Loss, Beginning Balance		9,744		11,298		11,610	10,590
Adoption of ASU 2016-13		10,936		9,744		11,668	11,610
Provision for loan losses (benefits)		2,694		1,747		58	2,708
Charge offs				(3,301)	[3]	(1,502)	(1,688)	[3]
Allowance for Credit Loss, Ending Balance		$ 10,936		$ 9,744		$ 11,668	$ 11,610

[1] Includes $0.7 million in loan specific allowances for loans deemed collateral dependent based on the excess amortized cost over the fair value of the underlying collateral.

[2] Includes $1.0 million in loan specific allowances for loans deemed collateral dependent based on the excess amortized cost over the fair value of the underlying collateral. In addition, $1.4 million of the CECL allowance is excluded from this table because it relates to unfunded commitments and has been recorded as a liability under accounts payable and accrued liabilities in our condensed consolidated balance sheet.

[3] Charge-offs result from either loan repayments where the proceeds are less than the principal outstanding or transfers to investment in real property at the time that we take ownership of the property where the fair values of the underlying collateral are less than the principal outstanding.

[4] CECL allowance related to unfunded commitments is presented as a liability under accounts payable and accrued liabilities in our condensed consolidated balance sheet.