Other Financial Information - Current Assets and Current Liabilities (Details 3) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Wireless spectrum licenses	Sep. 30, 2013 Wireless spectrum licenses	Jul. 28, 2014 Wireless spectrum licenses	Nov. 03, 2014 Wireless spectrum licenses Subsequent event type	Sep. 30, 2014 Wireless spectrum licenses Fair value inputs, Level 3
Schedule of Other Current Assets and Selected Current Liabilities
Impairment of indefinite-lived intangible assets			$ 14	$ 14
Other Current Assets
Prepaid expenses	260	266
Materials, supplies and inventory	134	167
Assets held for sale	54	26					39
Deferred activation and installation charges	105	94
Other	38	44
Total other current assets	591	597
Selected Current Liabilities
Accounts payable	1,069	1,111
Other Current Liabilities
Accrued rent	33	52
Legal reserves	18	273
Other	173	189
Total other current liabilities	224	514
Current Liabilities
Book overdraft balance	77	88
Capital expenditures incurred but not yet paid	120	140
Sales Price per Sales Agreement
Sale price specified in definitive sales agreement					39
Disposed long-lived assets, contract sales price						$ 39