Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Fair Value Of Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Interest expense reclassified from other comprehensive income (less than for 2019)	$ 100
Other comprehensive loss - change in value of interest rate swaps	(397)	$ (438)	$ 2,599
Prepaid expenses and other assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value of interest rate swaps	100
Fair Value, Measurements, Recurring \| Interest Rate Swap
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value of interest rate swaps	130	0
Accumulated Other Comprehensive Income (loss)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive loss - change in value of interest rate swaps	(397)	(438)	$ 2,599
Accumulated Other Comprehensive Income (loss) \| Equity Method Investee
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other comprehensive loss - change in value of interest rate swaps	900	400
Mortgage Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Mortgage payable	$ 547,247	$ 475,308
Hoboken \| Mortgage Payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Number of interest rate swap agreements	2
Notional amount of interest rate swap agreements	$ 56,500
Mortgage payable	$ 56,500
Fixed interest rate of derivative instrument	3.67%