Fair Value Measurements (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	$ 46	$ 77
U.S. government agency securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	260	309
U.S. government agency securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	260	309
Foreign government agency securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	13	55
Foreign government agency securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	13	55
Corporate debt securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	381	472
Corporate debt securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	381	472
Commercial paper | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	148	55
Commercial paper | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	148	55
Certificates of deposit | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15
Certificates of deposit | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15
U.S. treasury securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	50	99
U.S. treasury securities | Fair value on a recurring basis | Level 1
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	50	99
U.S. municipal securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15	23
U.S. municipal securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15	23
Asset-backed securities Automobile loan related | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	424	397
Asset-backed securities Automobile loan related | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	424	397
Asset-backed securities Credit card related | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	93	149
Asset-backed securities Credit card related | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	93	149
Asset-backed securities Equipment lease related | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	70	38
Asset-backed securities Equipment lease related | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	70	38
Asset-backed securities Other asset-backed securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	17	8
Asset-backed securities Other asset-backed securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	17	8
Auction rate securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	8	7
Auction rate securities | Fair value on a recurring basis | Level 3
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	8	7
Other securities | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	61	29
Other securities | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	61	29
Foreign currency forward/option contracts | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	17	38
Derivative instruments - liabilities	114	82
Foreign currency forward/option contracts | Fair value on a recurring basis | Level 1
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	15	36
Derivative instruments - liabilities	114	82
Foreign currency forward/option contracts | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	2	2
Commodity price swap contracts | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - liabilities	1	5
Commodity price swap contracts | Fair value on a recurring basis | Level 1
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - liabilities	1	5
Interest rate swap contracts | Fair value on a recurring basis | Fair Value
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	29	39
Interest rate swap contracts | Fair value on a recurring basis | Level 2
Assets and Liabilities Measured on Recurring Basis
Derivative instruments - assets	29	39
Fair value on a recurring basis | Fair Value | Investments
Assets and Liabilities Measured on Recurring Basis
Investments	7	21
Fair value on a recurring basis | Level 1 | Investments
Assets and Liabilities Measured on Recurring Basis
Investments	7	21
Asset-backed securities:
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 604