Commitments And Contingencies (Narrative) (Details) item in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) state entity item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Regulatory Commitments [Abstract]
Number of states of operation | state	28
Operating Leases [Abstract]
Term Of Lease Arrangements Lower Range	1 year
Term Of Lease Arrangements Upper Range	99 years
Rental expense	$ 119	$ 100	$ 84
FCC Inquiry [Member]
Regulatory Commitments [Abstract]
Number of carriers with tariff pricing plans under review | entity	4
CAF Phase II [Member]
Regulatory Commitments [Abstract]
Annual support offered by the Federal Communications Commission	$ 280
Number of households to be serviced under regulatory funded programs | item	654
Verizon Transaction [Member]
Regulatory Commitments [Abstract]
Annual support offered by the Federal Communications Commission	$ 49
Number of households to be serviced under regulatory funded programs | item	115