Investments in Unconsolidated Real Estate Joint Ventures (Joint Venture Fees) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Management, Leasing and other services [Line Items]
Fees received	$ 1,372	$ 1,443
Management and Marketing Fee [Member]
Management, Leasing and other services [Line Items]
Fees received	509	541
Leasing and other fees [Member]
Management, Leasing and other services [Line Items]
Fees received	56	20
Expense reimbursements from unconsolidated joint ventures [Member]
Management, Leasing and other services [Line Items]
Fees received	$ 807	$ 882