Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended				12 Months Ended
	Mar. 28, 2014	Sep. 26, 2014	Sep. 27, 2013 Employee	Sep. 28, 2012	Sep. 26, 2014 Cercla Sites and One Past Facility	Sep. 26, 2014 Cercla Sites and One Past Facility Minimum	Sep. 26, 2014 Cercla Sites and One Past Facility Maximum	Sep. 26, 2014 Other Sites	Sep. 26, 2014 Other Sites Minimum	Sep. 26, 2014 Other Sites Maximum	Sep. 26, 2014 Siemens AG Strategic Global Partnership	Apr. 30, 2012 Siemens AG Strategic Global Partnership	Sep. 26, 2014 CPTC Loan
Commitments And Contingencies [Line Items]
Long term accrued product warranty costs		$ 2,000,000	$ 14,100,000
Minimum rentals under operating leases fiscal year 2015		20,500,000
Minimum rentals under operating leases fiscal year 2016		16,400,000
Minimum rentals under operating leases fiscal year 2017		12,500,000
Minimum rentals under operating leases fiscal year 2018		8,100,000
Minimum rentals under operating leases fiscal year 2019		5,600,000
Operating leases future minimum payments due thereafter		10,000,000
Rental expenses		28,700,000	26,000,000	24,900,000
Commitment outstanding													4,700,000
Fixed fee committed											6,000,000	10,000,000
License fee committed											18,900,000	20,000,000
Fixed Cost Commitments		4,300,000
Contingent consideration liabilties		7,500,000	2,500,000
Environmental cleanup costs, third-party claim costs, project management costs and legal costs		1,200,000	1,000,000	1,600,000
Estimated environmental remediation costs, minimum					1,700,000			5,900,000
Estimated environmental remediation costs, maximum					9,900,000			36,300,000
Estimated time frames to resolve contingency related to environmental remediation contingencies, years						1 year	30 years		1 year	30 years
Amount accrued for environmental remediation expense					1,700,000			8,100,000
Estimated environmental remediation costs, best estimate, undiscounted								10,000,000
Discount rate for environmental remediation costs, net of inflation								4.00%
Receivables of past and future environmental-related expenditures		2,200,000	2,400,000
Actual damages found by jury				40,000,000
Court ordered amount				102,000,000
Enhanced damages				80,000,000
Prejudgment interest to the damages award				13,000,000
Attorneys fee added to the judgement				9,000,000
Full settlement of the lawsuit to the University of Pittsburgh				35,600,000
Loss Contingency Accrual				5,000,000
Litigation settlement	25,130,000	25,130,000
Prepaid Royalties	5,500,000
Number of employees accepted the voluntary retirement program			85
Restructuring charges incurred			$ 6,700,000