Investments in Unconsolidated Real Estate Joint Ventures (Joint Venture Fees) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Management, Leasing and other services [Line Items]
Fees received	$ 724	$ 1,245	$ 2,168	$ 2,587
Management and Marketing Fee [Member]
Management, Leasing and other services [Line Items]
Fees received	143	561	685	1,128
Leasing and other fees [Member]
Management, Leasing and other services [Line Items]
Fees received	15	9	35	40
Expense reimbursements from unconsolidated joint ventures [Member]
Management, Leasing and other services [Line Items]
Fees received	$ 566	$ 675	$ 1,448	$ 1,419