Notes Receivable and Current Expected Credit Losses (Schedule of Interest on the Mezzanine Loans) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	$ 3,568	$ 4,116
Mezzanine Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	3,459	4,013
Other Notes Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	109	103
City Park 2 | Mezzanine Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	19	0
Interlock Commercial | Mezzanine Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	2,826	3,075
Nexton Multifamily | Mezzanine Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	614	0
Solis Apartments at Interlock | Mezzanine Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	$ 0	$ 938