Pension Plans and Other Postretirement Benefits - Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 24, 2017	Jun. 25, 2016	Jun. 24, 2017	Jun. 25, 2016
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 96	$ 130	$ 288	$ 400
Amortization of prior service credits	0	(100)	0	(300)
Amortization of net loss (gain)	(98)	(74)	(292)	(223)
Net periodic benefit cost	(2)	(44)	(4)	(123)
Pension Benefits [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	1,041	1,260	3,123	3,781
Expected return on plan assets	(537)	(854)	(1,611)	(2,563)
Amortization of net loss (gain)	1,301	1,304	3,901	3,913
Net periodic benefit cost	$ 1,805	$ 1,710	$ 5,413	$ 5,131