Acquisitions (Estimated Fair Values Of Assets Acquired And Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified					3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Jan. 31, 2013 Zenprise, Inc. [Member]	Jul. 31, 2012 Bytemobile [Member]	Mar. 31, 2013 Minimum [Member] Zenprise, Inc. [Member]	Mar. 31, 2013 Minimum [Member] Bytemobile [Member]	Mar. 31, 2013 Maximum [Member] Zenprise, Inc. [Member]	Mar. 31, 2013 Maximum [Member] Bytemobile [Member]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Current assets			$ 10,943	$ 58,392
Other assets			668	7,406
Property and equipment			431	2,484
Deferred tax assets, non-current			33,125	39,976
Intangible assets			69,200	248,900
Goodwill	1,761,824	1,518,219	251,128	223,556
Assets acquired			365,495	580,714
Current liabilities assumed			8,475	62,390
Long-term liabilities assumed			3,107	4,487
Deferred tax liabilities, non-current			26,919	108,703
Net assets acquired			$ 326,994	$ 405,134
Weighted Average Asset Life					1 year	1 year	7 years	9 years