Schedule II Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 28, 2012
Allowance for Doubtful Accounts
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 14,735	$ 14,386	$ 6,034
Charged to Bad Debt Expense	7,150	5,984	10,350
Write-Offs/ Adjustments Charged to Allowance	(1,568)	(5,635)	(1,998)
Balance at End of Period	20,317	14,735	14,386
Valuation Allowance of Deferred Tax Assets
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	60,704	45,751	46,924
Increases	8,319	14,953	0
Deductions	(1,555)	0	(1,173)
Balance at End of Period	$ 67,468	$ 60,704	$ 45,751