CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 121,016	$ 106,787	$ 148,735	$ 143,955
Other comprehensive income:
Amortization of net actuarial losses and prior service credits into earnings	552	757	1,104	1,514
Other comprehensive income	552	757	1,104	1,514
Total comprehensive income	$ 121,568	$ 107,544	$ 149,839	$ 145,469

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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