Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Oct. 02, 2015	Sep. 26, 2014	Sep. 27, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Research and development asset acquired fair value	$ 10,600	$ 2,000
Amortization expense for intangible assets	8,443	$ 4,779	$ 4,332
Future amortization expense, fiscal year 2016	13,100
Future amortization expense, fiscal year 2017	13,400
Future amortization expense, fiscal year 2018	9,600
Future amortization expense, fiscal year 2019	9,000
Future amortization expense, fiscal year 2020	7,700
Future amortization expense, thereafter	$ 9,200