Statement of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net revenues	$ 81,326	$ 89,348	$ 255,841	$ 246,435
Cost of goods sold	55,811	63,565	179,156	171,614
Gross profit	25,515	25,783	76,685	74,821
Operating expenses:
Research, development and engineering	6,289	7,894	20,487	23,034
Selling, general and administrative	10,191	10,028	31,668	30,654
Amortization of acquired intangible assets	1,419	3,425	4,545	7,096
Total operating expenses	17,899	21,347	56,700	60,784
Operating income	7,616	4,436	19,985	14,037
Other income (expense):
Interest income	57	40	153	116
Interest expense	(392)	(458)	(1,124)	(1,151)
Other income (expense), net	108	(801)	2,481	(2,136)
Income before income tax provision	7,389	3,217	21,495	10,866
Provision for income tax	(767)	(2,665)	(5,551)	(4,952)
Net income	$ 6,622	$ 552	$ 15,944	$ 5,914
Net income per share:
Basic	$ 0.21	$ 0.02	$ 0.51	$ 0.19
Diluted	$ 0.21	$ 0.02	$ 0.50	$ 0.19
Cash dividends per common share	$ 0.035	$ 0.03	$ 0.10	$ 0.09
Weighted average shares used in per share calculation:
Basic	31,585	31,192	31,488	31,088
Diluted	32,231	32,032	32,173	31,838