CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Oct. 01, 2016		Oct. 03, 2015		Sep. 27, 2014
Income Statement [Abstract]
Net revenue	$ 627,192		$ 536,471		$ 568,569
Cost of sales	340,463		277,379		295,015
Gross profit	286,729		259,092		273,554
Selling, general and administrative	141,816		131,808		113,514
Research and development	92,374		90,033		83,056
Operating expenses	234,190		221,841		196,570
Income from operations	52,539		37,251		76,984
Interest income	3,318		1,637		1,197
Interest expense	(1,107)		(1,183)		(1,048)
Income from operations before income taxes	54,750		37,705		77,133
Income tax expense / (benefit)	7,638		(12,934)		14,145
Net income	$ 47,112		$ 50,639		$ 62,988
Net income per share:
Basic (in dollars per share)	$ 0.67	[1]	$ 0.67	[1]	$ 0.82
Diluted (in dollars per share)	$ 0.67	[1]	$ 0.67	[1]	$ 0.81
Weighted average shares outstanding:
Basic (in shares)	70,477		75,414		76,396
Diluted (in shares)	70,841		75,659		77,292

[1] EPS for the year may not equal the sum of quarterly EPS due to changes in weighted share calculations.