Income Taxes - Components of Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred income tax assets:
Accrued expenses	$ 322	$ 349
Deferred revenues	557	370
Capitalization of costs	1,661	1,843
Pension adjustment	2,921	2,883
Stock grant expense	2,211	2,500
State deferred taxes	0	116
Book deferred gains	1,034	1,176
Joint venture allocations	587	533
Provision for additional capitalized costs	699	699
Interest rate swap	1,769	810
Other	209	39
Total deferred income tax assets	11,970	11,318
Deferred income tax liabilities:
Deferred gains	490	490
Depreciation	3,533	2,892
Cost of sales allocations	872	872
Joint venture allocations	6,592	5,070
Straight line rent	548	590
Prepaid expenses	340	333
State deferred taxes	383	208
Other	137	150
Total deferred income tax liabilities	12,895	10,605
Net deferred income tax (liability) asset	(925)	713
Allowance for deferred tax assets	0	0
Deferred Tax Liabilities, Net	$ (925)
Net deferred taxes		$ 713