Consolidated Statements Of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 01, 2017	Apr. 02, 2016	Apr. 01, 2017	Apr. 02, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (1,104)	$ (5,173)	$ (10,245)	$ (29,065)
Other comprehensive income (loss), net of tax:
Unrealized hedge gain (loss) arising during the period, net of tax of $0.1 million and $0 million in the second quarter of 2017 and 2016, respectively, and $0.4 million and $0 million in the first six months of 2017 and 2016, respectively	(515)	(5,637)	2,522	(3,994)
Net hedge (gain) loss reclassified into earnings, net of tax of $0.1 million and $0 in the second quarter of 2017 and 2016, respectively, and $0.1 million and $0 million in the first six months of 2017 and 2016, respectively	(496)	13	(852)	(833)
Change in unrealized gain (loss) on hedging instruments	(1,011)	(5,624)	1,670	(4,827)
Foreign currency translation adjustment, net of tax of $0 for each period	4,992	15,247	(13,660)	4,743
Unrealized gain (loss) on marketable securities	68	0	(71)	0
Amortization of net actuarial pension loss included in net income, net of tax of $0.2 million in both the first quarter of 2017 and 2016, and $0.4 million and $0.3 million in the first six months of 2017 and 2016, respectively	574	400	1,090	802
Change in unamortized pension income (loss) during the period related to changes in foreign currency	(312)	(881)	1,378	(331)
Total other comprehensive income (loss)	4,311	9,142	(9,593)	387
Comprehensive income (loss)	$ 3,207	$ 3,969	$ (19,838)	$ (28,678)