Property, Plant, & Equipment (Property, Pland And Equipment, Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 25,541	$ 17,801
Construction work in progress	903	379
Less: Accumulated depreciation	(10,639)	(9,308)
Property, plant and equipment, net	14,902	8,493
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	235	151
Buildings and Leasehold Improvements Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 2,300	1,327
Estimated useful lives	41 years
General Support Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 1,495	1,146
General Support Member | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	17 years
General Support Member | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Central Office Electronic Circuit Equipment Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 7,683	6,244
Central Office Electronic Circuit Equipment Member | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	18 years
Central Office Electronic Circuit Equipment Member | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Poles Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 995	712
Estimated useful lives	30 years
Cable and Wire Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 10,267	7,280
Cable and Wire Member | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	25 years
Cable and Wire Member | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	15 years
Conduit Member
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 1,611	515
Estimated useful lives	55 years
Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 52	$ 47
Other [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	25 years
Other [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	12 years