Intangible Assets and Goodwill (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	May 24, 2013	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2013	Aug. 31, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, weighted average useful life	4 years 10 months 24 days
Intangible assets, amortization expense		$ 700,000	$ 300,000	$ 1,400,000	$ 1,100,000
Goodwill impairment loss				0
Purchased Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible asset, amount		7,800,000		7,800,000
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired finite-lived intangible asset, amount		$ 200,000		$ 200,000