CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 24, 2017	Jun. 25, 2016	Jun. 24, 2017	Jun. 25, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (29,716)	$ (29,598)	$ 88,585	$ 74,679
Other comprehensive income:
Net unrealized (losses) on cash flow hedges	0	(107)	(10)	(47)
Reclassification of realized losses on cash flow hedges into earnings	0	252	215	844
Amortization of net actuarial losses and prior service credits into earnings	1,203	1,130	3,609	3,390
Other comprehensive income	1,203	1,275	3,814	4,187
Total comprehensive (loss) income	$ (28,513)	$ (28,323)	$ 92,399	$ 78,866

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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