Goodwill and Other Acquired Intangible Assets (Schedule Of Carrying Values Of Amortized Acquired Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Nov. 30, 2011
Acquired Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization, intangible assets subject to amortization	$ (243,830)	$ (206,846)
Total intangible assets, Gross Carrying Amount	367,091	304,104
Total intangible assets, net	123,261	97,258
Developed technologies
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	182,152	146,289
Accumulated Amortization, intangible assets subject to amortization	(118,992)	(102,034)
Total intangible assets subject to amortization	63,160	44,255
Customer base
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	59,525	56,165
Accumulated Amortization, intangible assets subject to amortization	(43,328)	(37,376)
Total intangible assets subject to amortization	16,197	18,789
Patents/core technologies
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	28,295	27,922
Accumulated Amortization, intangible assets subject to amortization	(24,198)	(21,542)
Total intangible assets subject to amortization	4,097	6,380
Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	12,777	9,771
Accumulated Amortization, intangible assets subject to amortization	(8,251)	(7,077)
Total intangible assets subject to amortization	4,526	2,694
Non-compete agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	580	580
Accumulated Amortization, intangible assets subject to amortization	(580)	(580)
Total intangible assets subject to amortization	0	0
Maintenance agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, intangible assets subject to amortization	83,762	61,677
Accumulated Amortization, intangible assets subject to amortization	(48,481)	(38,237)
Total intangible assets subject to amortization	35,281	23,440
In-process research and development
Acquired Finite-Lived Intangible Assets [Line Items]
In-process research and development, Gross Carrying Amount	0	1,700
In-process research and development, Net Carrying Amount	$ 0	$ 1,700