Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income / (Loss) [Member]	Retained Earnings (Accumulated Deficit) [Member]	Treasury Stock [Member]	Total
Balance at Apr. 01, 2017	$ 248	$ 312,474	$ (9,823)	$ 448,693	$ 34,548	$ 717,044
Balance (in shares) at Apr. 01, 2017	24,757,803				(667,931)
Net income				21,809		21,809
Share-based compensation		3,228				3,228
Repurchase of common stock					$ (2,288)	(2,288)
Repurchase of common stock (in shares)					(22,711)
Exercise of equity awards	$ 1	6,106				6,107
Exercise of equity awards (in shares)	124,424
Change in net prior service cost and actuarial losses, net of taxes of $58			196			196
Issuance of restricted stock
Issuance of restricted stock (in shares)	62,070
Impact from adoption of ASU 2014-09				1,144		1,144
Currency translation adjustments			4,445			4,445
Balance at Jul. 01, 2017	$ 249	321,808	(5,182)	471,646	$ (36,836)	751,685
Balance (in shares) at Jul. 01, 2017	24,944,297				(690,642)
Balance at Apr. 01, 2017	$ 248	312,474	(9,823)	448,693	$ 34,548	717,044
Balance (in shares) at Apr. 01, 2017	24,757,803				(667,931)
Net income						36,632
Currency translation adjustments						4,420
Balance at Sep. 30, 2017	$ 249	325,517	(5,011)	486,469	$ (37,904)	769,320
Balance (in shares) at Sep. 30, 2017	24,948,512				(701,068)
Balance at Jul. 01, 2017	$ 249	321,808	(5,182)	471,646	$ (36,836)	751,685
Balance (in shares) at Jul. 01, 2017	24,944,297				(690,642)
Net income				14,823		14,823
Share-based compensation		3,402				3,402
Repurchase of common stock					$ (1,068)	(1,068)
Repurchase of common stock (in shares)					(10,426)
Exercise of equity awards		307				307
Exercise of equity awards (in shares)	5,000
Change in net prior service cost and actuarial losses, net of taxes of $58			196			196
Issuance of restricted stock
Issuance of restricted stock (in shares)	(785)
Currency translation adjustments			(25)			(25)
Balance at Sep. 30, 2017	$ 249	325,517	(5,011)	486,469	$ (37,904)	769,320
Balance (in shares) at Sep. 30, 2017	24,948,512				(701,068)
Balance at Mar. 31, 2018	$ 251	339,148	(2,285)	536,978	$ (39,540)	834,552
Balance (in shares) at Mar. 31, 2018	25,123,694				(713,687)
Net income				27,467		27,467
Share-based compensation		3,766				3,766
Repurchase of common stock					$ (1,491)	(1,491)
Repurchase of common stock (in shares)					(11,865)
Exercise of equity awards	$ 2	6,416				6,418
Exercise of equity awards (in shares)	100,142
Change in net prior service cost and actuarial losses, net of taxes of $58			$ 194			$ 194
Issuance of restricted stock
Issuance of restricted stock (in shares)	87,345
Impact from adoption of ASU 2014-09				$ (277)		$ (277)
Currency translation adjustments			(4,061)			(4,061)
Balance at Jun. 30, 2018	$ 253	349,330	(6,152)	564,168	$ (41,031)	866,568
Balance (in shares) at Jun. 30, 2018	25,311,181				(725,552)
Balance at Mar. 31, 2018	$ 251	339,148	(2,285)	536,978	$ (39,540)	834,552
Balance (in shares) at Mar. 31, 2018	25,123,694				(713,687)
Net income						57,578
Currency translation adjustments						(3,621)
Balance at Sep. 29, 2018	$ 255	366,358	(5,518)	594,279	$ (43,071)	912,303
Balance (in shares) at Sep. 29, 2018	25,509,691				(741,074)
Balance at Jun. 30, 2018	$ 253	349,330	(6,152)	564,168	$ (41,031)	866,568
Balance (in shares) at Jun. 30, 2018	25,311,181				(725,552)
Net income				30,111		30,111
Share-based compensation		4,039				4,039
Repurchase of common stock					$ (2,040)	(2,040)
Repurchase of common stock (in shares)					(15,522)
Exercise of equity awards	$ 2	12,989				12,991
Exercise of equity awards (in shares)	192,300
Change in net prior service cost and actuarial losses, net of taxes of $58			194			194
Issuance of restricted stock
Issuance of restricted stock (in shares)	6,210
Income tax benefit on exercise of non-qualified common stock options
Currency translation adjustments			440			440
Balance at Sep. 29, 2018	$ 255	$ 366,358	$ (5,518)	$ 594,279	$ (43,071)	$ 912,303
Balance (in shares) at Sep. 29, 2018	25,509,691				(741,074)