Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2017
Postretirement Benefits Additional (Textual) [Abstract]
Interest cost	$ 2,478	$ 2,252	$ 2,274
Amortization of prior service cost	1,556	1,556	1,556
Service cost	958	1,085	1,046
Amortization of net actuarial loss	218	336	142
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	356	0	0
Total	5,566	5,229	5,018
Liabilities related to postretirement benefit plan	$ 69,300	$ 60,800
Discounted rate for benefit plan	2.70%	4.10%
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of insurance contracts	$ 73,849	$ 73,721
2019	2,300
2020	2,500
2021	2,600
2022	2,900
2023	3,200
2024-2028	20,800
Supplemental Nonqualified Unfunded Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	2,100	(900)	3,900
Defined Benefit Plan, Benefit Obligation, Benefits Paid	1,800	1,600	1,500
Cash surrender value of insurance contracts	44,700	44,400
Unfunded Death Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)	900	(300)	$ 1,500
Cash surrender value of insurance contracts	18,400	$ 18,200
Defined Benefit Plan, Plan Assets, Benefits Paid	$ 1,700