Acquisitions (Narrative) (Details) (USD $)	9 Months Ended			1 Months Ended	9 Months Ended	1 Months Ended	3 Months Ended	9 Months Ended		1 Months Ended	9 Months Ended			1 Months Ended	3 Months Ended				9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2013		Sep. 30, 2013 Infrastructure [Member]	Jan. 31, 2013 Zenprise, Inc. [Member]	Sep. 30, 2013 Zenprise, Inc. [Member]	Jul. 31, 2012 Bytemobile [Member]	Sep. 30, 2013 Bytemobile [Member]	Sep. 30, 2013 Bytemobile [Member]	Sep. 30, 2012 Bytemobile [Member]	Apr. 30, 2012 Podio [Member]	Sep. 30, 2012 Podio [Member]	Apr. 30, 2012 Podio [Member] Product Related Technologies [Member]	Apr. 30, 2012 Podio [Member] Other Intangible Assets [Member]	Sep. 30, 2013 Series of Individually Immaterial Business Acquisitions [Member]	Sep. 30, 2013 Series of Individually Immaterial Business Acquisitions [Member]	Sep. 30, 2012 Series of Individually Immaterial Business Acquisitions [Member] acquisitions	Jun. 30, 2012 Series of Individually Immaterial Business Acquisitions [Member] acquisitions	Mar. 31, 2012 Series of Individually Immaterial Business Acquisitions [Member]	Sep. 30, 2013 Series of Individually Immaterial Business Acquisitions [Member]	Mar. 31, 2012 Series of Individually Immaterial Business Acquisitions [Member] Product Related Technologies [Member]	Sep. 30, 2012 Series of Individually Immaterial Business Acquisitions [Member] Infrastructure [Member] acquisitions	Sep. 30, 2012 Series of Individually Immaterial Business Acquisitions [Member] Q1 [Member]	Sep. 30, 2012 Series of Individually Immaterial Business Acquisitions [Member] Q2 [Member]
Finite-Lived Intangible Assets [Line Items]
Total consideration in business acquisition				$ 324,000,000		$ 399,500,000				$ 43,600,000				$ 5,300,000		$ 5,300,000	$ 15,400,000	$ 24,600,000
Cash acquired in business combination				2,900,000		5,600,000				1,700,000							200,000	600,000
Transaction costs				600,000		2,100,000				500,000						200,000	400,000	500,000
Transaction costs expensed during period					100,000				2,100,000		500,000				200,000				200,000			400,000	400,000.0
Goodwill acquired	251,766,000	[1]	249,392,000							24,500,000								23,100,000
Identifiable intangible assets acquired				69,200,000		248,900,000				24,600,000		20,700,000	3,900,000							11,000,000
Stock units converted and assumed										127,668						13,487	66,459	13,481
Stock options converted and assumed				285,817														12,017
Net adjustment to preliminary purchase price allocation							2,700,000	4,100,000
Number of privately-held businesses acquired																2	2				1
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High														$ 3,000,000	$ 3,000,000				$ 3,000,000

[1] Amounts relate to Zenprise and 2013 Other Acquisition. See Note 4 for more information regarding the Company’s acquisitions.