Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2016
Postretirement Benefits Additional (Textual) [Abstract]
Interest cost	$ 2,252	$ 2,274	$ 2,285
Amortization of prior service cost	1,556	1,556	1,556
Service cost	1,085	1,046	1,045
Amortization of net actuarial loss	336	142	79
Total	5,229	5,018	4,965
Liabilities related to postretirement benefit plan	$ 60,800	$ 66,500
Discounted rate for benefit plan	4.10%	3.50%
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of insurance contracts	$ 73,721	$ 75,236
2019	2,200
2020	2,500
2021	3,100
2022	3,200
2023	3,500
2024-2028	20,700
Supplemental Nonqualified Unfunded Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	(900)	3,900	400
Defined Benefit Plan, Benefit Obligation, Benefits Paid	1,600	1,500	1,400
Cash surrender value of insurance contracts	44,400	46,800
Unfunded Death Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	(300)	1,500	$ 200
Cash surrender value of insurance contracts	$ 18,200	$ 18,500