Derivative Financial Instruments (Schedule of Changes in Fair Value of Derivatives) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Derivative [Line Items]        
Tax expense recognized in Other comprehensive income (loss) $ (14) $ 3 $ (24) $ 7
Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (9) (2) (14) (1)
Gain (Loss) Recognized in Earnings (Loss) 24 (3) 25 (8)
Equity Method Investments' Derivative [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss)   1    
Gain (Loss) Recognized in Earnings (Loss)   1   1
Interest Rate Swap [Member]
        
Derivative [Line Items]        
Tax expense recognized in Other comprehensive income (loss)   1 4 3
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss) 0 (2) [1] (1) [2] (1) [3]
Cross Currency Interest Rate Contract [Member]
        
Derivative [Line Items]        
Tax expense recognized in Other comprehensive income (loss) 3   4  
Cross Currency Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (9) [4] 0 (13) [5] 0
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss) 0 0 0 0
Interest Expense [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Earnings (Loss) (1) [6] (3) [6] (3) [6] (8) [6]
Other Income [Member] | Cross Currency Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Earnings (Loss) 25 [7] 0 28 [7] 0
Foreign Currency Gain (Loss) [Member] | Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Earnings (Loss) (4) [8] (10) [8] (9) [8] (14) [8]
Net Investment Hedging [Member]
        
Derivative [Line Items]        
Gain (Loss) Recognized in Other Comprehensive Income (Loss) 9 0 9 0
Gain (Loss) Recognized in Earnings (Loss) $ 0 $ 0 $ 0 $ 0
[1] Excludes $1 million of gains associated with the Company's equity method investments' derivative activity and $1 million of tax expense recognized in Other comprehensive income (loss).
[2] Excludes $4 million of tax expense recognized in Other comprehensive income (loss).
[3] Excludes $3 million of tax expense recognized in Other comprehensive income (loss).
[4] Excludes $3 million of tax benefit recognized in Other comprehensive income (loss).
[5] Excludes $4 million of tax benefit recognized in Other comprehensive income (loss).
[6] Reclassified from Accumulated other comprehensive income (loss), net to Interest income (expense) in the unaudited interim consolidated statements of operations.
[7] Included in Other income (expense), net for non-operating activity or Interest income (expense) for coupon interest in the unaudited interim consolidated statements of operations.
[8] Included in Foreign exchange gain (loss), net for operating activity or Other income (expense), net for non-operating activity in the unaudited interim consolidated statements of operations.