Acquisitions (Narrative) (Details) (USD $)					1 Months Ended	6 Months Ended	1 Months Ended	3 Months Ended		6 Months Ended		1 Months Ended	6 Months Ended			3 Months Ended			6 Months Ended		3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Infrastructure [Member]	Dec. 31, 2012 Infrastructure [Member]	Jan. 31, 2013 Zenprise, Inc. [Member]	Jun. 30, 2013 Zenprise, Inc. [Member]	Jul. 31, 2012 Bytemobile [Member]	Jun. 30, 2013 Bytemobile [Member]	Jun. 30, 2012 Bytemobile [Member]	Jun. 30, 2013 Bytemobile [Member]	Jun. 30, 2012 Bytemobile [Member]	Apr. 30, 2012 Podio [Member]	Jun. 30, 2012 Podio [Member]	Apr. 30, 2012 Podio [Member] Product Related Technologies [Member]	Apr. 30, 2012 Podio [Member] Other Intangible Assets [Member]	Sep. 30, 2012 2012 Other Acquisitions [Member] acquisitions	Jun. 30, 2012 2012 Other Acquisitions [Member] acquisitions	Mar. 31, 2012 2012 Other Acquisitions [Member]	Jun. 30, 2012 2012 Other Acquisitions [Member]	Mar. 31, 2012 2012 Other Acquisitions [Member] Product Related Technologies [Member]	Sep. 30, 2012 2012 Other Acquisitions [Member] Infrastructure [Member] acquisitions	Jun. 30, 2012 Q1 2012 Other Acquisitions [Member]	Jun. 30, 2012 Q3 2012 Other Acquisitions [Member]	Jun. 30, 2012 Q3 2012 Other Acquisitions [Member]
Finite-Lived Intangible Assets [Line Items]
Total consideration in business acquisition					$ 324,000,000		$ 399,500,000					$ 43,600,000				$ 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	200,000
Transaction costs					600,000		2,100,000					500,000				200,000	400,000	500,000	400,000
Transaction costs expensed during period						100,000			2,100,000		2,100,000		500,000						400,000			400,000	0	0
Goodwill acquired	1,762,714,000	1,518,219,000	1,405,948,000	1,158,580,000	249,392,000		223,908,000					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	66,459.000000	13,481
Stock options converted and assumed					285,817													12,017
Net adjustment to preliminary purchase price allocation								$ 400,000		$ 1,400,000
Number of privately-held businesses acquired																2	2				1