Subsequent Events (Summary of Repayment of Mortgages) (Details) - USD ($) $ in Thousands		12 Months Ended
	Mar. 16, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Subsequent Event [Line Items]
Outstanding principal amount repaid		$ 98,074	$ 928	$ 7,660
Subsequent Event [Member] | Mortgage Loans [Member] | Dixie Valley [Member]
Subsequent Event [Line Items]
Property Name	Dixie Valley
Date of payoff	Jan. 21, 2022
Outstanding principal amount repaid	$ 6,798
Subsequent Event [Member] | Mortgage Loans [Member] | Eastside Junction [Member]
Subsequent Event [Line Items]
Property Name	Eastside Junction
Date of payoff	Mar. 01, 2022
Outstanding principal amount repaid	$ 5,787
Subsequent Event [Member] | Mortgage Loans [Member] | White City [Member]
Subsequent Event [Line Items]
Property Name	White City
Date of payoff	Mar. 07, 2022
Outstanding principal amount repaid	$ 47,579
Subsequent Event [Member] | Mortgage Loans [Member] | Pentucket Shopping Center [Member]
Subsequent Event [Line Items]
Property Name	Pentucket Shopping Center
Date of payoff	Mar. 15, 2022
Outstanding principal amount repaid	$ 14,700