Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	$ 87,016	$ 88,238
Accumulated Amortization	(73,142)	(65,462)
Net	13,874	22,776
Amortization of intangible assets	8,500	8,200	$ 9,600
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2017	6,932
2018	4,197
2019	2,107
2020	634
2021	2
Thereafter	2
Net	13,874	22,776
Existing technology
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	70,664	71,365
Accumulated Amortization	(61,133)	(55,452)
Net	$ 9,531	15,913
Remaining amortization period	2 years 1 month 6 days
Amortization of intangible assets	$ 6,000	6,300	$ 7,500
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Net	9,531	15,913
Customer lists
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	15,968	16,099
Accumulated Amortization	(11,658)	(9,661)
Net	$ 4,310	6,438
Remaining amortization period	2 years 9 months 18 days
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Net	$ 4,310	6,438
Trade name
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	384	399
Accumulated Amortization	(351)	(349)
Net	$ 33	50
Remaining amortization period	3 years 1 month 6 days
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Net	$ 33	50
In-process research and development
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	0	375
Accumulated Amortization	0	0
Net	0	375
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Net	0	375
Foreign Exchange
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of intangible assets	$ 400	$ 2,900