Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	$ 16,558	$ 15,814
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(8,359)	(7,678)
Net	8,199	8,136
Depreciation expense	659	706	775
Land
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	195	195
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	0	0
Net	195	195
Land Improvements
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	73	73
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(43)	(40)
Net	30	33
Facility and Leasehold Improvements
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	2,050	2,046
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(1,074)	(978)
Net	976	1,068
Network infrastructure
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	8,342	8,189
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(3,058)	(2,817)
Net	5,284	5,372
Operating Equipment
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	5,506	4,978
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(3,997)	(3,680)
Net	1,509	1,298
Furniture, Fixtures and Office Equipment
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	249	228
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(166)	(142)
Net	83	86
Other
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	21	21
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(21)	(21)
Net	0	0
Construction-in-Progress
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Gross	122	84
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	0	0
Net	$ 122	$ 84