Statement of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Income Statement Abstract
Net revenues	$ 80,041	$ 91,727	$ 280,823	$ 266,512
Cost of goods sold	56,889	62,647	191,158	176,131
Gross profit	23,152	29,080	89,665	90,381
Operating expenses:
Research, development and engineering	6,368	6,684	19,805	20,293
Selling, general and administrative	10,827	10,595	32,142	31,471
Amortization of acquisition-related intangible assets	640	1,630	1,885	5,476
Restructuring charges	0	515	0	566
Total operating expenses	17,835	19,424	53,832	57,806
Operating income	5,317	9,656	35,833	32,575
Other income (expense):
Interest income	85	67	246	219
Interest expense	(282)	(389)	(859)	(1,204)
Other income, net	862	625	2,129	1,443
Income before income tax provision	5,982	9,959	37,349	33,033
Provision for income tax	(311)	(2,653)	(10,755)	(12,320)
Net income	$ 5,671	$ 7,306	$ 26,594	$ 20,713
Net income per share
Basic	$ 0.18	$ 0.23	$ 0.85	$ 0.66
Diluted	$ 0.18	$ 0.23	$ 0.82	$ 0.65
Weighted average shares used in per share calculation
Basic	31,203	31,096	31,335	31,210
Diluted	32,238	32,071	32,505	31,877