Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 01, 2015	Feb. 23, 2014
Changes in accumulated other comprehensive loss:
Total recognized in accumulated other comprehensive loss	$ (4,099)	$ (2,302)
Pension Benefits [Member]
Net periodic benefit cost (income):
Service cost	2,128	2,159
Interest cost	11,840	13,761
Expected return on plan assets	(12,717)	(13,843)
Amortization of prior service benefit	(16)	(17)
Amortization of actuarial loss	3,160	2,696
Curtailment loss	335	232
Net settlement loss	0	60
Net periodic benefit cost	4,730	5,048
Changes in accumulated other comprehensive loss:
Amortization of prior service benefit	16	17
Amortization of actuarial loss	(3,160)	(2,696)
Curtailment gain (loss)	(335)	0
Net settlement loss	0	(25)
Total recognized in accumulated other comprehensive loss	(3,479)	(2,704)
Total recognized in net periodic benefit cost and accumulated other comprehensive loss	1,251	2,344
Postretirement Benefits [Member]
Net periodic benefit cost (income):
Service cost	63	68
Interest cost	1,147	1,338
Expected return on plan assets	0	0
Amortization of prior service benefit	0	(1)
Amortization of actuarial loss	1,128	989
Curtailment loss	0	700
Net settlement loss	0	0
Net periodic benefit cost	2,338	3,094
Changes in accumulated other comprehensive loss:
Amortization of prior service benefit	0	1
Amortization of actuarial loss	(1,128)	(989)
Curtailment gain (loss)	0	0
Net settlement loss	0	0
Total recognized in accumulated other comprehensive loss	(1,128)	(988)
Total recognized in net periodic benefit cost and accumulated other comprehensive loss	$ 1,210	$ 2,106