Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax liabilities:
Property and equipment	$ 5,145	$ 4,333
Intangible assets	19,324	17,640
Prepaid expenses	350	317
Total deferred tax liabilities	24,819	22,290
Deferred tax assets:
Allowance for doubtful accounts	118	116
Compensation	906	1,058
Other accrued liabilities	63	44
Deferred Tax Assets, Gross, Total	1,087	1,218
Less: valuation allowance	0	0
Total net deferred tax assets	1,087	1,218
Net deferred tax liabilities	23,732	21,072
Current portion of deferred tax assets	303	300
Non-current portion of deferred tax liabilities	(24,035)	(21,372)
Net deferred tax liabilities	$ (23,732)	$ (21,072)