Goodwill And Other Intangible Assets (Schedule Of Change In Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Goodwill [Roll Forward]
Balance at January 1, 2015	$ 1,796,851
Additions	61,738	[1]
Other	(509)
Balance at March 31, 2015	1,858,080
Enterprise and Service Provider [Member]
Goodwill [Roll Forward]
Balance at January 1, 2015	1,434,369
Additions	61,738
Other	(509)	[2]
Balance at March 31, 2015	1,495,598
Mobility Apps [Member]
Goodwill [Roll Forward]
Balance at January 1, 2015	362,482
Additions	0
Other	0
Balance at March 31, 2015	$ 362,482

[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.