Property, Plant and Equipment (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended							9 Months Ended	12 Months Ended									3 Months Ended	12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2012 Support assets	Dec. 31, 2011 Support assets	Dec. 31, 2012 Construction in progress	Dec. 31, 2011 Construction in progress	Dec. 31, 2012 Fiber, conduit and other outside plant	Dec. 31, 2011 Fiber, conduit and other outside plant	Dec. 31, 2012 Central office and other network electronics	Dec. 31, 2011 Central office and other network electronics	Mar. 31, 2011 Predecessor	Dec. 31, 2010 Predecessor	Dec. 31, 2012 Change in estimates of capitalized labor Adjustments	Dec. 31, 2012 Change in estimates of capitalized labor Adjustments Minimum	Dec. 31, 2012 Change in estimates of capitalized labor Adjustments Maximum	Dec. 31, 2011 Change in estimates of fair value of buildings at the acquisition date Retrospective adjustment Support assets	Dec. 31, 2011 Change in estimates of fair value of buildings at the acquisition date Retrospective adjustment Construction in progress	Dec. 31, 2011 Change in estimates of fair value of buildings at the acquisition date Retrospective adjustment Fiber, conduit and other outside plant	Dec. 31, 2011 Change in estimates of fair value of buildings at the acquisition date Retrospective adjustment Central office and other network electronics
Change in accounting estimates
Labor capitalized as an asset																					$ 40	$ 55
Operating expenses								(5,436)	(6,943)									(1,630)	(6,788)		40	55
Depreciation expense								914	1,176									393	1,652	(52)
Property, plant and equipment	9,242				8,420			8,420	9,242	2,428	2,449	372	201	3,475	3,247	2,611	2,155						(36)	38	8	30
Net income	$ 241	$ 212	$ 178	$ 218	$ 179	$ 199	$ 165	$ 543	$ 849									$ 299	$ 1,082	$ 32	$ 25	$ 34