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Fair Value Of Financial Instruments (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) agreement	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) agreement	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income (loss)		$ 458		$ (6,487)
Amount reclassified from other comprehensive income to interest expense	$ (200)		$ (700)
Accumulated other comprehensive loss
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income (loss)		$ 458		$ (6,487)
Accumulated other comprehensive loss \| One of our equity method investees
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive income (loss)	200		500
Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ (1,977)		$ (1,977)		$ (4,711)
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 (loss)	$ 400		$ 2,700
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	$ 2,000		$ 2,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	0		0		0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	(1,977)		(1,977)		(4,711)
Fair Value, Inputs, Level 3 [Member] \| Fair Value, recurring \| Interest rate swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Derivative Liability	$ 0		$ 0		$ 0