SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands		12 Months Ended
		Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Allowance for Doubtful Accounts [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period		$ 2,441	$ 3,520	$ 11,122
Charged (credited) to Costs and Expenses		3,545	1,146	(397)
Other Additions		0	0	0
Deductions	[1]	(2,942)	(2,225)	(7,205)
Balance at End of Period		3,044	2,441	3,520
Valuation Allowance of Deferred Tax Assets [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period		58,782	54,045	51,864
Charged (credited) to Costs and Expenses		406	4,737	2,181
Other Additions		0	0	0
Deductions	[1]	0	0	0
Balance at End of Period		$ 59,188	$ 58,782	$ 54,045

[1] Represents amounts that did not impact earnings.