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Fair Value Of Financial Instruments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) agreement	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) agreement	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive loss	$ (493)	$ (399)	$ (6,945)	$ (608)
Amount reclassified from other comprehensive loss to interest expense (less than)			(200)
Accumulated other comprehensive loss
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive loss	(493)	$ (399)	(6,945)	$ (608)
Accumulated other comprehensive loss \| One of our equity method investees
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive loss	100		800
Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ (6,059)		$ (6,059)
Derivative Asset					$ 130
Fair Value, recurring \| Interest rate swap \| One of our equity method investees
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Number of interest rate swap agreements \| agreement	2		2
Mortgage payable \| Hoboken
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Number of interest rate swap agreements	2		2
Other comprehensive loss	$ 500		$ 6,200
Notional amount of derivative liability	56,500		56,500
Mortgage payable	$ 56,500		$ 56,500
Fixed interest rate on derivative	3.67%		3.67%
Other liabilities and deferred credits
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ 6,100		$ 6,100
Fair Value, Inputs, Level 1 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	0		0
Derivative Asset					0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	(6,059)		(6,059)
Derivative Asset					130
Fair Value, Inputs, Level 3 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ 0		$ 0
Derivative Asset					$ 0