Restructuring Charges (Narrative) (Details)	3 Months Ended			6 Months Ended
	May 31, 2016 USD ($)	Nov. 30, 2015 USD ($) Segments	May 31, 2015 USD ($) facility	May 31, 2016 USD ($)	May 31, 2015 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 331,000		$ 3,810,000	$ 265,000	$ 6,153,000
Restructuring reserve	1,167,000	$ 3,361,000		1,167,000
2015 Restructuring Activities [Member]
Restructuring Cost and Reserve [Line Items]
Number of facilities closed | facility			2
Restructuring expenses	100,000			(22,000)
Restructuring reserve	812,000	$ 2,617,000		812,000
Number of operating segments | Segments		3
2015 Restructuring Activities [Member] | Other accrued liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	800,000			800,000
2012 - 2014 Restructuring Activities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses			$ 0		1,300,000
2012 - 2014 Restructuring Activities [Member] | Other accrued liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	100,000			100,000
Level 3 [Member] | Nonrecurring Basis [Member]
Restructuring Cost and Reserve [Line Items]
Long-lived assets at fair value			100,000		100,000
Telerik AD [Member]
Restructuring Cost and Reserve [Line Items]
Impairment of long-lived assets			4,000,000
Telerik AD [Member] | 2015 Restructuring Activities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	200,000		$ 3,900,000	274,000	$ 4,900,000
Restructuring reserve	258,000	$ 518,000		258,000
Telerik AD [Member] | 2015 Restructuring Activities [Member] | Other accrued liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 300,000			$ 300,000