CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Net revenues	$ 856,903	$ 881,176	$ 856,907
Cost of revenues	417,788	439,806	422,233
Gross profit	439,115	441,370	434,674
Operating expenses:
Research, development, and engineering	84,193	88,318	90,408
Selling, general, and administrative	229,390	223,830	221,299
(Gain) loss, net from litigation settlements	(420)	4,255	(1,234)
Restructuring and other related charges (credits)	2,451	(109)	16,160
Total operating expenses	315,614	316,294	326,633
Operating income	123,501	125,076	108,041
Interest expense	(29,297)	(29,230)	(25,149)
Other non-operating income and (expense), net	6,023	5,819	(716)
Income before income taxes	100,227	101,665	82,176
Income tax expense	101,096	19,066	13,784
Net income	$ (869)	$ 82,599	$ 68,392
Earnings per common share:
Basic (in dollars per share)	$ (0.03)	$ 2.56	$ 2.00
Diluted (in dollars per share)	$ (0.03)	$ 2.51	$ 1.96
Shares used in computing earnings per common share:
Basic (in shares)	32,345	32,279	34,127
Diluted (in shares)	32,345	32,963	34,938
Cash dividends declared per common share (in dollars per share)	$ 0.60	$ 0.60	$ 0.60