Income Taxes (Details) - USD ($) $ / shares in Units, $ 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	Sep. 29, 2012
Deferred Tax Assets and Liabilities [Line Items]
Net income	$ 27,302	$ 13,264	$ 18,413	$ 17,430	$ 19,097	$ 12,999	$ 15,307	$ 11,703	$ 76,409	$ 59,106	$ 66,355
Other income (expense), net									(1,179)	2,353	(1,403)
Deferred tax assets, valuation allowance increase/decrease									1,200
Currently payable:
Federal									(932)	2,492	(1,796)
State									108	92	(141)
Foreign									32,189	26,885	27,152
Currently payable total									31,365	29,469	25,215
Deferred:
Federal									(4,327)	(2,815)	(4,022)
State									(200)	(111)	(16)
Foreign									(3,679)	(6,430)	(4,036)
Deferred total									(8,206)	(9,356)	(8,074)
Provision for (benefit from) income taxes									23,159	20,113	17,141
Components of income (loss) before income taxes
United States									(13,293)	821	(7,142)
Foreign									112,861	78,398	90,638
Income before income taxes									$ 99,568	$ 79,219	$ 83,496
Reconciliation of income tax expense (benefit) at U.S. Federal statutory rate
U.S. Federal statutory rate									35.00%	35.00%	35.00%	35.00%
Federal statutory tax expense (benefit)									$ 34,849	$ 27,727	$ 29,223
Valuation allowance									635	841	534
Foreign taxes at rates less than U.S. rates, net									(10,558)	(6,974)	(8,219)
Stock-based compensation									2,150	1,326	1,292
State income taxes, net of federal income tax benefit									(38)	58	(143)
Research and development credit									(2,979)	(1,797)	(4,131)
Deferred compensation									(133)	(778)	(257)
Release of unrecognized tax benefits									(39)	(51)	(407)
Release of interest accrued for unrecognized tax benefits									(38)	(289)	(160)
Other									(690)	50	(591)
Provision for (benefit from) income taxes									$ 23,159	$ 20,113	$ 17,141
Effective tax rate									23.30%	25.40%	20.50%
effective tax rate on income before income taxes									23.30%
Deferred tax assets:
Reserves and accruals not currently deductible	31,067				29,060				$ 31,067	$ 29,060
Operating loss carryforwards and tax credits	53,386				65,643				53,386	65,643
Deferred service revenue	2,144				2,097				2,144	2,097
Inventory capitalization	1,827				1,616				1,827	1,616
Stock-based compensation	6,128				6,573				6,128	6,573
Competent authority offset to transfer pricing tax reserves	4,328				4,328				4,328	4,328
Other	2,418				0				2,418	0
Deferred Tax Assets, Gross	101,298				109,317				101,298	109,317
Valuation allowance on deferred tax assets	(15,556)				(14,403)				(15,556)	(14,403)
Deferred Tax Assets, Net	85,742				94,914				85,742	94,914
Deferred tax liabilities:
Gain on issuance of stock by subsidiary	20,859				20,759				20,859	20,759
Depreciation and amortization	5,117				9,579				5,117	9,579
Accumulated translation adjustment	2,229				1,357				2,229	1,357
Other	0				5,012				0	5,012
Deferred Tax Liabilities	28,205				36,707				28,205	36,707
Net deferred tax assets	57,537				58,207				57,537	58,207
Classification of net deferred tax assets on consolidated balance sheets
Current deferred income tax assets	28,118				27,134				28,118	27,134
Current deferred income tax liabilities	(9)				(32)				(9)	(32)
Non-current deferred income tax assets	32,136				37,616				32,136	37,616
Non-current deferred income tax liabilities	(2,708)				(6,511)				(2,708)	(6,511)
Various tax attribute carryforwards
Foreign net operating loss carryforwards	53,386				65,643				53,386	65,643
Foreign tax credit carry forwards	11,500								11,500
Unrecognized Tax Benefits	22,538				$ 21,893				22,538	21,893	$ 21,378	$ 25,967
Gross unrecognized tax benefits	24,300								24,300
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	16,400								16,400
Tax benefit credit to APIC when recognized [Member]
Various tax attribute carryforwards
Foreign tax credit carry forwards	19,000								19,000
Foreign
Deferred Tax Assets and Liabilities [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration	17,100								17,100
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	900								900
Deferred tax assets:
Operating loss carryforwards and tax credits	18,000								18,000
Various tax attribute carryforwards
Foreign net operating loss carryforwards	18,000								18,000
Valuation allowance recorded against foreign net operating loss carryforwards	4,900								4,900
Increase (Decrease) in Income Taxes Payable									$ 2,800	$ 2,400	$ 2,100
Income Tax Holiday, Income Tax Benefits Per Share									$ 0.11	$ 0.10	$ 0.09
Federal
Various tax attribute carryforwards
Tax Credit Carryforward, Amount	900								$ 900
Federal | Subject to Expiration Dates
Various tax attribute carryforwards
R&D credit carryforwards	24,400								24,400
CALIFORNIA
Deferred Tax Assets and Liabilities [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	14,700								14,700
Deferred tax assets:
Operating loss carryforwards and tax credits	6,600								6,600
Various tax attribute carryforwards
Foreign net operating loss carryforwards	6,600								6,600
Tax Credit Carryforward, Amount	500								500
Valuation allowance, net of federal benefit, recorded against California R&D credit carryforwards	14,000								14,000
CALIFORNIA | Not Subject to Expiration Dates
Various tax attribute carryforwards
R&D credit carryforwards	22,200								22,200
federal tax authority [Member]
Deferred tax assets:
Operating loss carryforwards and tax credits	900								900
Various tax attribute carryforwards
Foreign net operating loss carryforwards	900								900
state tax authority [Member] [Member]
Deferred tax assets:
Operating loss carryforwards and tax credits	1,400								1,400
Various tax attribute carryforwards
Foreign net operating loss carryforwards	1,400								1,400
Other states besides California
Various tax attribute carryforwards
Valuation allowance, net of federal benefit, recorded against California R&D credit carryforwards	600								600
Other states besides California | Subject to Expiration Dates
Various tax attribute carryforwards
R&D credit carryforwards	$ 1,700								$ 1,700