Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net revenues	$ 21,144	$ 14,443	$ 62,520	$ 38,948
Cost of revenues	10,749	7,993	31,642	21,564
Gross margin	10,395	6,450	30,878	17,384
Operating expenses:
Selling expense	2,841	1,747	7,849	5,560
Engineering and product development expense	1,334	1,316	4,012	3,825
General and administrative expense	3,620	2,799	10,550	8,525
Restructuring and other charges	51	161	303	207
Total operating expenses	7,846	6,023	22,714	18,117
Operating income (loss)	2,549	427	8,164	(733)
Other income (loss)	(17)	6	2	(44)
Earnings (loss) before income tax expense (benefit)	2,532	433	8,166	(777)
Income tax expense (benefit)	357	(25)	1,170	(262)
Net earnings (loss)	$ 2,175	$ 458	$ 6,996	$ (515)
Net earnings (loss) per common share - basic (in dollars per share)	$ 0.21	$ 0.04	$ 0.67	$ (0.05)
Weighted average common shares outstanding - basic (in shares)	10,496,188	10,269,995	10,422,851	10,247,779
Net earnings (loss) per common share - diluted (in dollars per share)	$ 0.20	$ 0.04	$ 0.65	$ (0.05)
Weighted average common shares and common share equivalents outstanding - diluted (in shares)	10,792,290	10,287,562	10,694,351	10,247,779