CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Revenue	$ 12,362			$ 12,768			$ 38,432	$ 35,273
Costs of goods sold, inclusive of depreciation and amortization	8,827			8,828			29,555	26,359
Gross margin	3,535			3,940			8,877	8,914
Operating Expenses:
Selling, general and administrative	2,134			2,074			6,436	5,715
Interest expense	31			28			88	80
Total operating expenses	2,165			2,102			6,524	5,795
Income before income tax provision	1,370			1,838			2,353	3,119
Income tax provision	238			381			409	624
Net income	$ 1,132	$ 714	$ 98	$ 1,457	$ 707	$ 331	$ 1,944	$ 2,495
Basic
Net Income per share (in dollars per share)	$ 0.49			$ 0.63			$ 0.84	$ 1.10
Diluted
Net income per share (in dollars per share)	$ 0.47			$ 0.61			$ 0.82	$ 1.07