ACQUISITIONS - Supplemental Pro Forma Data (Detail) (USD $)	12 Months Ended
	Sep. 30, 2012	Oct. 02, 2011	Oct. 03, 2010
Business Acquisition [Line Items]
Acquisition cost	$ 7,300,000	$ 6,300,000
Credit facility issuance costs	41,790,000	17,218,000	0
Increase in valuation allowance	194,700,000		15,600,000
Net sales	1,019,329,000	1,095,481,000	806,331,000
Net income (loss)	10,002,000	65,804,000	(89,868,000)
Net income (loss) per share
Basic	$ 0.12	$ 0.78	$ (1.11)
Diluted	$ 0.11	$ 0.77	$ (1.11)
Zarlink Semiconductor, Inc
Business Acquisition [Line Items]
Credit facility issuance costs	34,000,000
Actel Corporation
Business Acquisition [Line Items]
Credit facility issuance costs	14,200,000
Tax Valuation Allowance
Business Acquisition [Line Items]
Increase in valuation allowance		5,000,000
Fair Value Adjustment to Inventory [Member]
Business Acquisition [Line Items]
Cost of goods sold	$ 9,200,000	$ 5,500,000