Intangible Assets and Goodwill (Narrative) (Details)		3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 02, 2014 USD ($)	May. 31, 2015 USD ($)	May. 31, 2014 USD ($)	May. 31, 2015 USD ($) Segments	May. 31, 2014 USD ($)	Nov. 30, 2014 USD ($)
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization expense		$ 7,300,000	$ 700,000	$ 15,100,000	$ 1,400,000
Number of reporting units | Segments				3
Goodwill impairment loss						$ 0
Telerik AD [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 123,100,000
Acquired intangible assets, useful life	5 years			5 years
Intangible assets, amortization expense				$ 12,300,000
Telerik AD [Member] | Existing Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 64,800,000
Telerik AD [Member] | Customer-related and other [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	47,100,000
Telerik AD [Member] | Trademarks and trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 11,200,000