Intangible Assets and Goodwill (Schedule Of Intangible Assets) (Details) - USD ($) $ in Thousands	May 31, 2017	Nov. 30, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 213,428	$ 192,628
Accumulated Amortization	(126,564)	(111,801)
Net Book Value	86,864	80,827
Purchased technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	129,786	109,886
Accumulated Amortization	(76,477)	(68,116)
Net Book Value	53,309	41,770
Customer-related [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	67,702	67,602
Accumulated Amortization	(41,033)	(35,852)
Net Book Value	26,669	31,750
Trademarks and trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	15,940	15,140
Accumulated Amortization	(9,054)	(7,833)
Net Book Value	$ 6,886	$ 7,307