Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2015

Summary Of Significant Accounting Policies [Abstract]

Schedule Of Revenue From External Customers

	For the three months ended				For the nine months ended
	September 30,				September 30,
($ in millions)	2015		2014		2015		2014
Voice services	$	500	$	472	$	1,540	$	1,426
Data and Internet services		589		469		1,748		1,393
Other		134		76		404		232
Customer revenue		1,223		1,017		3,692		3,051
Switched access and subsidy		201		124		471		391
Total revenue	$	1,424	$	1,141	$	4,163	$	3,442