Goodwill And Other Intangible Assets (Schedule Of Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Intangible Assets [Abstract]
Gross carrying amount	$ 1,051,620		$ 1,051,620		$ 1,037,663
Accumulated amortization	804,228		804,228		754,245
Intangible assets, fair value	247,392		247,392
Product Related Intangible Assets [Member]
Intangible Assets [Abstract]
Gross carrying amount	602,060		602,060		589,847
Accumulated amortization	499,231		499,231		476,141
Other [Member]
Intangible Assets [Abstract]
Gross carrying amount	449,560		449,560		447,816
Accumulated amortization	304,997		$ 304,997		$ 278,104
Minimum [Member]
Statement [Line Items]
Intangible asset life			3 years
Maximum [Member]
Statement [Line Items]
Intangible asset life			7 years
Maximum [Member] | Patents [Member]
Statement [Line Items]
Intangible asset life			10 years
Cost of net revenues [Member] | Product Related Intangible Assets [Member]
Intangible Assets [Abstract]
Amortization expense	15,000	$ 19,100	$ 45,700	$ 56,200
Operating Expense [Member] | Other [Member]
Intangible Assets [Abstract]
Amortization expense	$ 7,400	12,500	$ 22,100	33,000
Enterprise and Service Provider Division [Member] | ByteMobile [Member]
Intangible Assets [Abstract]
Impairment of intangible assets				65,400
Enterprise and Service Provider Division [Member] | ByteMobile [Member] | Amortization and Impairment of Other Intangible Assets [Member]
Intangible Assets [Abstract]
Impairment of intangible assets				64,400
Enterprise and Service Provider Division [Member] | ByteMobile [Member] | Amortization of Product Related Intangibles [Member]
Intangible Assets [Abstract]
Impairment of intangible assets				1,000
Estimate of Fair Value Measurement [Member] | Enterprise and Service Provider Division [Member] | ByteMobile [Member]
Intangible Assets [Abstract]
Intangible assets, fair value		$ 27,600		$ 27,600