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Fair Value Of Financial Instruments (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) agreement	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) agreement	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income for the three months and loss for the nine months	$ 458	$ (111)	$ (6,487)	$ (719)
Amount reclassified from other comprehensive loss to interest expense (less than)	(200)		(400)
Accumulated other comprehensive loss
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income for the three months and loss for the nine months	458	$ (111)	(6,487)	$ (719)
Accumulated other comprehensive loss \| One of our equity method investees
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income for the three months and loss for the nine months	200		600
Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ (5,745)		$ (5,745)
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 income for the three months and loss for the nine months	$ 300		$ 5,900
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	$ 5,700		$ 5,700
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	(5,745)		(5,745)
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