Income Taxes (Significant components of the Company's deferred tax liabilities and assets) (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Deferred tax liabilities:
Property and equipment	$ 4,242,000	$ 4,802,000
Intangible assets	21,425,000	20,442,000
Prepaid expenses	405,000	426,000
Total deferred tax liabilities	26,072,000	25,670,000
Deferred tax assets:
Allowance for doubtful accounts	43,000	89,000
Compensation	1,093,000	824,000
Other accrued liabilities	134,000	150,000
Deferred Tax Assets, Gross, Total	1,270,000	1,063,000
Less: valuation allowance	0	0
Total net deferred tax assets	1,270,000	1,063,000
Net deferred tax liabilities	24,802,000	24,607,000
Current portion of deferred tax assets	361,000	150,000
Non-current portion of deferred tax liabilities	(25,163,000)	(24,757,000)
Net deferred tax liabilities	$ (24,802,000)	$ (24,607,000)