CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 25, 2017	Mar. 26, 2016	Mar. 25, 2017	Mar. 26, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 83,812	$ 92,011	$ 118,301	$ 104,277
Other comprehensive income:
Net unrealized (losses) gains on cash flow hedges	(5)	(117)	(10)	60
Reclassification of realized losses on cash flow hedges into earnings	15	259	215	592
Amortization of net actuarial losses and prior service credits into earnings	1,203	1,301	2,406	2,260
Other comprehensive income	1,213	1,443	2,611	2,912
Total comprehensive income	$ 85,025	$ 93,454	$ 120,912	$ 107,189

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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