Business Segments and International Operations (Revenue from External Customers from Different Geographical Areas) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2018	Aug. 31, 2017
Revenue from External Customer [Line Items]
Segment revenue	$ 95,683	$ 97,310	$ 285,832	$ 281,493
North America
Revenue from External Customer [Line Items]
Segment revenue	52,212	55,703	154,676	157,438
EMEA
Revenue from External Customer [Line Items]
Segment revenue	33,422	31,830	101,769	92,320
Latin America
Revenue from External Customer [Line Items]
Segment revenue	4,341	5,009	13,058	15,669
Asia Pacific
Revenue from External Customer [Line Items]
Segment revenue	$ 5,708	$ 4,768	$ 16,329	$ 16,066