Statement of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Net revenues	$ 89,348	$ 63,812	$ 246,435	$ 213,130
Cost of goods sold	63,565	44,841	171,614	146,682
Gross profit	25,783	18,971	74,821	66,448
Operating expenses:
Research, development and engineering	7,894	6,784	23,034	20,749
Selling, general and administrative	10,028	9,150	30,654	29,448
Amortization of acquired intangible assets	3,425	559	7,096	1,683
Total operating expenses	21,347	16,493	60,784	51,880
Operating income	4,436	2,478	14,037	14,568
Other income (expense):
Interest income	40	113	116	281
Interest expense	(458)	(228)	(1,151)	(719)
Other income (expense), net	(801)	(392)	(2,136)	515
Income before income tax provision	3,217	1,971	10,866	14,645
Provision for income tax	(2,665)	(782)	(4,952)	(5,092)
Net income	$ 552	$ 1,189	$ 5,914	$ 9,553
Net income per share:
Basic	$ 0.02	$ 0.04	$ 0.19	$ 0.31
Diluted	$ 0.02	$ 0.04	$ 0.19	$ 0.30
Cash dividends per common share	$ 0.03	$ 0.03	$ 0.09	$ 0.03
Weighted average shares used in per share calculation:
Basic	31,192	31,005	31,088	31,222
Diluted	32,032	31,487	31,838	31,917