Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 25, 2019	Aug. 26, 2018	Aug. 25, 2019	Aug. 26, 2018
Net periodic benefit cost:
Net periodic benefit cost	$ 4,868	$ 1,744	$ 14,647	$ 5,211
Pension Benefits [Member]
Net periodic benefit cost:
Net periodic benefit cost	3,975	819	11,968	2,434
Postretirement Benefits [Member]
Net periodic benefit cost:
Net periodic benefit cost	$ 893	$ 925	$ 2,679	$ 2,777