v2.4.0.6
Wireless Licenses, Goodwill And Other Intangible Assets (Composition Of Other Intangible Assets, Net) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Mar. 31, 2012
Y
Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]    
Gross Amount $ 13,619 $ 13,626
Accumulated Amortization (7,875) (7,748)
Net Amount 5,744 5,878
Customer Lists (6 To 13 Years) [Member]
    
Finite-Lived Intangible Assets [Line Items]    
Gross Amount 3,389 3,529
Accumulated Amortization (2,009) (2,052)
Net Amount 1,380 1,477
Minimum useful life for finite-lived intangible assets, years 6  
Maximum useful life for finite-lived intangible assets, years 13  
Non-Network Internal-Use Software (3 To 7 Years) [Member]
    
Finite-Lived Intangible Assets [Line Items]    
Gross Amount 9,663 9,536
Accumulated Amortization (5,642) (5,487)
Net Amount 4,021 4,049
Minimum useful life for finite-lived intangible assets, years 3  
Maximum useful life for finite-lived intangible assets, years 7  
Other (2 To 25 Years) [Member]
    
Finite-Lived Intangible Assets [Line Items]    
Gross Amount 567 561
Accumulated Amortization (224) (209)
Net Amount $ 343 $ 352
Minimum useful life for finite-lived intangible assets, years 2  
Maximum useful life for finite-lived intangible assets, years 25