CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 24, 2017	Jun. 30, 2018	Jun. 24, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (16,595)	$ (29,716)	$ 127,360	$ 88,585
Other comprehensive income:
Net unrealized (losses) on cash flow hedges	0	0	0	(10)
Reclassification of realized losses on cash flow hedges into earnings	0	0	0	215
Amortization of net actuarial losses and prior service credits into earnings	757	1,203	2,271	3,609
Other comprehensive income	757	1,203	2,271	3,814
Total comprehensive (loss) income	$ (15,838)	$ (28,513)	$ 129,631	$ 92,399

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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