CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Income Statement [Abstract]
Net sales	$ 19,568	$ 14,413
Cost of sales	12,763	8,902
Gross profit	6,805	5,511
Selling, general, and administrative expenses	2,733	3,272
Engineering expense	1,819	3,469
Operating income (loss)	2,253	(1,230)
Interest expense	18	173
Other expense - net	21	25
Income (loss) before income taxes	2,214	(1,428)
Income tax provision (benefit)	841	(600)
Net income (loss)	$ 1,373	$ (828)
Earnings (loss) per common share:
Basic net income (loss) per share	$ 0.14	$ (0.09)
Diluted net income (loss) per share	$ 0.14	$ (0.09)
Weighted-average basic shares outstanding	9,568,000	9,493,000
Weighted-average diluted shares outstanding	9,667,000	9,493,000