Mortgage Loans Payable and Unsecured Credit Facility (Schedule of Debt and Finance Lease Obligations Related to Continuing Operations) (Parenthetical) (Details) - Revolving Credit Facility [Member]	3 Months Ended
	Mar. 31, 2022 Term
Debt Instrument [Line Items]
Line of credit facility extension allowed period	1 year
Line of credit facility extension allowed term	2