CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 47,857	$ 41,444
Costs of goods sold, inclusive of depreciation and amortization	35,772	31,447
Gross margin	12,085	9,997
Operating expenses:
Selling, general and administrative	7,743	7,845
Interest expense	107	77
Total operating expenses	7,850	7,922
Income before income tax provision	4,235	2,075
Income tax provision	737	758
Net income	$ 3,498	$ 1,317
Basic
Net income per share (in dollars per share)	$ 1.54	$ 0.58
Diluted
Net income per share (in dollars per share)	$ 1.49	$ 0.57