Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Jul. 01, 2012	Jul. 03, 2011	Jul. 01, 2012	Jul. 03, 2011
Income Taxes [Line Items]
Benefit for income taxes	$ 4,161,000	$ (3,986,000)	$ 8,533,000	$ (12,441,000)
US statutory rate			35.00%
Within the next twelve months
Income Taxes [Line Items]
Anticipated decrease in unrecognized tax benefits	$ 9,600,000		$ 9,600,000
Federal | Minimum
Income Taxes [Line Items]
Open tax year			2007
Federal | Maximum
Income Taxes [Line Items]
Open tax year			2011
State | Minimum
Income Taxes [Line Items]
Open tax year			2007
State | Maximum
Income Taxes [Line Items]
Open tax year			2011
Foreign Country | Minimum
Income Taxes [Line Items]
Open tax year			2007
Foreign Country | Maximum
Income Taxes [Line Items]
Open tax year			2011