Pensions and Postretirement Benefits (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2014	May 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Service costs incurred	$ 3,048	$ 2,608	$ 6,093	$ 5,206
Interest costs on projected benefit obligation	2,140	1,768	4,241	3,461
Expected return on plan assets	(2,134)	(1,903)	(4,224)	(3,724)
Amortization of prior service credit	(338)	(336)	(676)	(672)
Amortization of transitional obligation	11	0	22	0
Net periodic pension expense	2,727	2,137	5,456	4,271
United States Postretirement Benefit Plan of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service costs incurred	4	5	8	11
Interest costs on projected benefit obligation	103	100	206	200
Net periodic pension expense	$ 107	$ 105	$ 214	$ 211