Significant Transactions (Spectrum Licenses) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Subsequent Event [Line Items]
Purchases of spectrum licenses and other intangible assets	$ 1,844	$ 2,367
FCC Spectrum Auction [Member]
Subsequent Event [Line Items]
Aggregate bid price of spectrum licenses	1,800
Purchases of spectrum licenses and other intangible assets	1,400
Deposit provided to FCC	$ 400