Goodwill And Other Intangible Assets (Schedule Of Change In Goodwill) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($)
Goodwill [Roll Forward]
Balance at January 1, 2015	$ 1,796,851
Additions	161,325	[1]
Other	(740)
Balance at September 30, 2015	1,957,436
Enterprise and Service Provider [Member]
Goodwill [Roll Forward]
Balance at January 1, 2015	1,434,369
Additions	61,639
Other	(740)	[2]
Balance at September 30, 2015	1,495,268
Mobility Apps [Member]
Goodwill [Roll Forward]
Balance at January 1, 2015	362,482
Additions	99,686
Other	0
Balance at September 30, 2015	$ 462,168

[1] Amounts relate to 2015 acquisitions. See Note 4 for more information regarding the Company’s acquisitions.

[2] Amount relates to adjustments to the preliminary purchase price allocation associated with 2014 acquisitions.