Financial Instruments (Fair Values of Outstanding Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Derivative Assets:
Derivative Assets	$ 573	$ 232
Derivative Liabilities:
Derivative Liabilities	3	4
Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		145
Level 2 | Foreign exchange contracts | Accrued expenses and other current liabilities
Derivative Liabilities:
Derivative Liabilities		4
Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current and assets held for sale
Derivative Assets:
Derivative Assets	573
Level 2 | Foreign exchange contracts | Accrued expenses, and other current liabilities and liabilities held for sale
Derivative Liabilities:
Derivative Liabilities	3
Level 2 | Interest rate contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		87
Fair Value of Derivatives Designated as Hedging Instruments
Derivative Assets:
Derivative Assets	571	220
Derivative Liabilities:
Derivative Liabilities	0	0
Fair Value of Derivatives Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		133
Fair Value of Derivatives Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Accrued expenses and other current liabilities
Derivative Liabilities:
Derivative Liabilities		0
Fair Value of Derivatives Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current and assets held for sale
Derivative Assets:
Derivative Assets	571
Fair Value of Derivatives Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Accrued expenses, and other current liabilities and liabilities held for sale
Derivative Liabilities:
Derivative Liabilities	0
Fair Value of Derivatives Designated as Hedging Instruments | Level 2 | Interest rate contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		87
Derivatives Not Designated as Hedging Instruments
Derivative Assets:
Derivative Assets	2	12
Derivative Liabilities:
Derivative Liabilities	3	4
Derivatives Not Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		12
Derivatives Not Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Accrued expenses and other current liabilities
Derivative Liabilities:
Derivative Liabilities		4
Derivatives Not Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Prepaid revenue share, expenses and other assets, current and non-current and assets held for sale
Derivative Assets:
Derivative Assets	2
Derivatives Not Designated as Hedging Instruments | Level 2 | Foreign exchange contracts | Accrued expenses, and other current liabilities and liabilities held for sale
Derivative Liabilities:
Derivative Liabilities	3
Derivatives Not Designated as Hedging Instruments | Level 2 | Interest rate contracts | Prepaid revenue share, expenses and other assets, current and non-current
Derivative Assets:
Derivative Assets		$ 0