Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	$ 17,329	$ 16,558
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(9,089)	(8,359)
Net	8,240	8,199
Depreciation expense	727	659	706
Land
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	193	195
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	0	0
Net	193	195
Land Improvements
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	72	73
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(47)	(43)
Net	25	30
Facility and Leasehold Improvements
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	2,207	2,093
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(1,193)	(1,085)
Net	1,014	1,008
Network infrastructure
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	8,505	8,342
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(3,279)	(3,058)
Net	5,226	5,284
Operating Equipment
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	6,057	5,506
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(4,381)	(3,997)
Net	1,676	1,509
Furniture, Fixtures and Office Equipment
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	196	206
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(168)	(155)
Net	28	51
Other
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	22	21
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(21)	(21)
Net	1	0
Construction-in-Progress
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	77	122
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	0	0
Net	$ 77	$ 122