Restructuring Charges (Summary of Restructuring Activity) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2020	Aug. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 2,203,000
Costs incurred	$ 91,000	$ 801,000	1,826,000	$ 3,993,000
Cash disbursements			(3,131,000)
Translation adjustments and other			(16,000)
Ending Balance	882,000		882,000
2019 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			1,460,000
Costs incurred	0		109,000
Cash disbursements			(1,404,000)
Ending Balance	165,000		165,000
2017 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			552,000
Costs incurred			1,448,000
Cash disbursements			(1,326,000)
Translation adjustments and other			(15,000)
Ending Balance	659,000		659,000
Excess Facilities and Other Costs
Restructuring Reserve [Roll Forward]
Beginning Balance			196,000
Costs incurred			1,678,000
Cash disbursements			(1,148,000)
Translation adjustments and other			(16,000)
Ending Balance	710,000		710,000
Excess Facilities and Other Costs | 2019 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			0
Costs incurred			0
Cash disbursements			0
Ending Balance	0		0
Excess Facilities and Other Costs | 2017 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			5,000
Costs incurred			1,409,000
Cash disbursements			(747,000)
Translation adjustments and other			(15,000)
Ending Balance	652,000		652,000
Employee Severance and Related Benefits
Restructuring Reserve [Roll Forward]
Beginning Balance			2,007,000
Costs incurred			148,000
Cash disbursements			(1,983,000)
Translation adjustments and other			0
Ending Balance	172,000		172,000
Employee Severance and Related Benefits | 2019 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			1,460,000
Costs incurred			109,000
Cash disbursements			(1,404,000)
Ending Balance	165,000		165,000
Employee Severance and Related Benefits | 2017 Restructuring Activities
Restructuring Reserve [Roll Forward]
Beginning Balance			547,000
Costs incurred			39,000
Cash disbursements			(579,000)
Translation adjustments and other			0
Ending Balance	$ 7,000		$ 7,000