CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended
Dec. 24, 2016	Dec. 26, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 34,489	$ 12,266
Other comprehensive income:
Net unrealized (losses) gains on cash flow hedges	(5)	177
Reclassification of realized losses on cash flow hedges into earnings	200	333
Amortization of net actuarial losses and prior service credits into earnings	1,203	959
Other comprehensive income	1,398	1,469
Total comprehensive income	$ 35,887	$ 13,735

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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