CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net revenues	$ 226,534	$ 232,933	$ 640,760	$ 672,222
Cost of revenues	112,409	122,753	315,720	338,523
Gross profit	114,125	110,180	325,040	333,699
Operating expenses:
Research, development, and engineering	21,257	21,393	62,402	66,116
Selling, general, and administrative	56,196	56,919	170,125	169,581
(Gain) loss, net from litigation settlements	(15)	(103)	(295)	4,287
Restructuring and other related charges (credits)	(84)	113	2,438	(1,350)
Total operating expenses	77,354	78,322	234,670	238,634
Operating income	36,771	31,858	90,370	95,065
Interest expense	(7,341)	(7,322)	(21,904)	(21,867)
Other non-operating income and (expense), net	2,490	427	5,230	4,119
Income before income taxes	31,920	24,963	73,696	77,317
Income tax expense	81,424	2,742	84,419	14,235
Net income (loss)	$ (49,504)	$ 22,221	$ (10,723)	$ 63,082
Earnings (Loss) per common share:
Earnings (Loss) per common share:	$ (1.54)	$ 0.69	$ (0.33)	$ 1.96
Diluted (in dollars per share)	$ (1.54)	$ 0.68	$ (0.33)	$ 1.92
Shares used in computing earnings (loss) per common share:
Basic (in shares)	32,075	32,242	32,384	32,260
Diluted (in shares)	32,075	32,826	32,384	32,895
Cash dividends declared per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.45	$ 0.45