Business Combinations (Narrative) (Details) - USD ($)				12 Months Ended
	Dec. 02, 2014	May. 13, 2014	May. 24, 2013	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2013	Oct. 01, 2014
Business Acquisition [Line Items]
Goodwill				$ 369,985,000	$ 232,836,000	$ 224,286,000
Total stock-based compensation				24,004,000	24,873,000	21,399,000
Acquisition-related expenses				4,239,000	5,862,000	3,204,000
Total revenue				377,554,000	332,533,000	333,996,000
Income (loss) from continuing operations before income taxes				12,354,000	77,804,000	62,783,000
Intangible assets, amortization expense				29,600,000	3,700,000	2,100,000
Changes in fair value of contingent consideration obligation				(1,508,000)	89,000	9,000
Telerik AD [Member]
Business Acquisition [Line Items]
Total purchase consideration	$ 262,500,000
Total consideration paid to founders and key employees in restricted stock units	$ 10,500,000
Percent of total consideration deposited in escrow	10.00%
Identifiable intangible assets	$ 123,100,000			123,100,000
Goodwill	137,921,000			137,472,000
Total stock-based compensation				3,500,000
Acquisition-related expenses				$ 3,700,000
Deferred revenue, period for recognition				1 year
Earn-out provision				$ 2,500,000
Expense recognized related to contingent earn-out provisions				2,200,000
Total revenue				41,800,000
Income (loss) from continuing operations before income taxes				(54,100,000)
Intangible assets, amortization expense				$ 24,600,000
Pro forma amortization expense					123,100,000
Pro forma, Bulgaria statutory rate (as a percent)				10.00%
Pro forma, U.S. statutory rate (as a percent)				37.00%
Fair value of purchase consideration	251,953,000			$ 251,953,000
BravePoint Inc. [Member]
Business Acquisition [Line Items]
Goodwill							$ 2,257,000
Acquisition-related expenses				1,200,000	200,000
Equity interests (as a percent)							100.00%
Fair value of purchase consideration							$ 12,000,000
Modulus [Member]
Business Acquisition [Line Items]
Total purchase consideration		$ 15,000,000
Goodwill		$ 6,433,000
Acquisition-related expenses				$ 300,000
Equity interests (as a percent)		100.00%
Fair value of purchase consideration		$ 13,950,000
Purchase consideration, cash		12,500,000
Purchase consideration, contingent consideration		$ 2,500,000
Expected payout period		2 years
Contingent consideration		$ 1,500,000
Contingent consideration, discount rate				33.00%
Changes in fair value of contingent consideration obligation				$ 1,500,000
Rollbase [Member]
Business Acquisition [Line Items]
Total purchase consideration			$ 9,900,000
Identifiable intangible assets			7,960,000
Goodwill			$ 4,798,000
Earn-out provision				5,400,000
Expense recognized related to contingent earn-out provisions				700,000	$ 2,800,000	$ 1,900,000
Equity interests (as a percent)			100.00%
Fair value of purchase consideration			$ 9,879,000
Purchase consideration, cash			9,500,000
Purchase consideration, contingent consideration			$ 400,000
Expected payout period			2 years
Payments for contingent consideration liability				$ 2,700,000
Minimum [Member] | Modulus [Member]
Business Acquisition [Line Items]
Probability milestones associated with contingent consideration will be achieved				75.00%
Intellectual Property [Member] | Telerik AD [Member]
Business Acquisition [Line Items]
Identifiable intangible assets	64,800,000
Purchased Technology [Member] | BravePoint Inc. [Member]
Business Acquisition [Line Items]
Identifiable intangible assets							1,810,000
Purchased Technology [Member] | Modulus [Member]
Business Acquisition [Line Items]
Identifiable intangible assets		7,320,000
Purchased Technology [Member] | Rollbase [Member]
Business Acquisition [Line Items]
Weighted average amortization period for intangibles				5 years
Customer Relationships [Member] | Telerik AD [Member]
Business Acquisition [Line Items]
Identifiable intangible assets	47,100,000
Customer Relationships [Member] | Rollbase [Member]
Business Acquisition [Line Items]
Weighted average amortization period for intangibles				1 year
Trademarks and Trade Names [Member] | Telerik AD [Member]
Business Acquisition [Line Items]
Identifiable intangible assets	11,200,000
Customer-Related [Member] | BravePoint Inc. [Member]
Business Acquisition [Line Items]
Identifiable intangible assets							$ 4,110,000
Customer-Related [Member] | Modulus [Member]
Business Acquisition [Line Items]
Identifiable intangible assets		$ 190,000
Credit Agreement [Member]
Business Acquisition [Line Items]
Issuance of debt, face amount	$ 150,000,000