Segment and Geographic Information - Revenue and Long-Lived Assets by Geographical Areas (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 03, 2015	Jul. 04, 2015	Apr. 04, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Oct. 03, 2015	Sep. 27, 2014	Sep. 28, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales	$ 209,622	$ 188,502	$ 203,721	$ 200,615	$ 205,344	$ 196,517	$ 199,222	$ 193,556	$ 802,460	$ 794,639	$ 810,126
Total long-lived assets	131,412				137,522				131,412	137,522
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									213,483	202,205	188,204
Total long-lived assets	82,951				82,274				82,951	82,274
Foreign countries:
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									588,977	592,434	621,922
Total long-lived assets	48,461				55,248				48,461	55,248
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									135,674	124,765	156,152
South Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									195,589	167,473	185,737
GERMANY
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									75,474	86,023	93,855
Total long-lived assets	33,964				38,678				33,964	38,678
Europe, other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									53,027	64,648	58,500
Total long-lived assets	2,993				2,920				2,993	2,920
Asia-Pacific, Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									85,584	98,760	73,794
Total long-lived assets	$ 11,504				$ 13,650				11,504	13,650
Rest of World
Revenues from External Customers and Long-Lived Assets [Line Items]
Total sales									$ 43,629	$ 50,765	$ 53,884