Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2013
Postretirement Benefits Additional (Textual) [Abstract]
Interest cost	$ 2,270	$ 2,456	$ 2,078
Amortization of prior service cost	1,556	1,556	1,556
Service cost	1,142	1,184	1,504
Amortization of net actuarial loss	848	357	1,803
Total	5,816	5,553	6,941
Liabilities related to postretirement benefit plan	$ 60,800	$ 62,600
Discounted rate for benefit plan	3.60%	3.50%
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of insurance contracts	$ 67,786	$ 70,571
2014	1,700
2015	1,800
2016	2,700
2017	3,200
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	3,400
2018 - 2022	19,200
Supplemental Nonqualified Unfunded Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	(1,300)	1,800	3,100
Benefits paid	1,400	1,200	1,100
Cash surrender value of insurance contracts	45,700	48,100
Unfunded Death Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	(300)	700	$ 1,400
Cash surrender value of insurance contracts	$ 16,800	$ 17,100