CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (29,041)	$ (16,595)	$ 119,694	$ 127,360
Other comprehensive income:
Amortization of net actuarial losses and prior service credits into earnings	552	757	1,656	2,271
Other comprehensive income	552	757	1,656	2,271
Total comprehensive (loss) income	$ (28,489)	$ (15,838)	$ 121,350	$ 129,631

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

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