Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 2,088	$ 2,209
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	70	84
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	57	110
Fair value on a recurring basis | Fair Value | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	52	75
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	54	103
Fair value on a recurring basis | Fair Value | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	1	1
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	1
Fair value on a recurring basis | Fair Value | Interest rate swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	17	8
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	2	7
Fair value on a recurring basis | Fair Value | U.S. government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	148	234
Fair value on a recurring basis | Fair Value | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	120	125
Fair value on a recurring basis | Fair Value | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	796	781
Fair value on a recurring basis | Fair Value | Certificates of deposit/time deposits
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	48	40
Fair value on a recurring basis | Fair Value | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		60
Fair value on a recurring basis | Fair Value | Asset-backed securities Automobile loan related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	537	585
Fair value on a recurring basis | Fair Value | Asset-backed securities Credit card related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	222	180
Fair value on a recurring basis | Fair Value | Asset-backed securities Equipment lease related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	88	67
Fair value on a recurring basis | Fair Value | Asset-backed securities Other asset-backed securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	68	75
Fair value on a recurring basis | Fair Value | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	49	49
Fair value on a recurring basis | Fair Value | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		2
Fair value on a recurring basis | Fair Value | Auction rate securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	12	11
Fair value on a recurring basis | Fair Value | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	1	2
Fair value on a recurring basis | Level 1 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	52	75
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	54	103
Fair value on a recurring basis | Level 1 | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	1	1
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	1
Fair value on a recurring basis | Level 1 | Interest rate swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 1 | U.S. government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Certificates of deposit/time deposits
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		0
Fair value on a recurring basis | Level 1 | Asset-backed securities Automobile loan related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Asset-backed securities Credit card related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Asset-backed securities Equipment lease related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Asset-backed securities Other asset-backed securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	49	49
Fair value on a recurring basis | Level 1 | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		0
Fair value on a recurring basis | Level 1 | Auction rate securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 1 | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	1	2
Fair value on a recurring basis | Level 2 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 2 | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0
Fair value on a recurring basis | Level 2 | Interest rate swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	17	8
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	2	7
Fair value on a recurring basis | Level 2 | U.S. government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	148	234
Fair value on a recurring basis | Level 2 | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	120	125
Fair value on a recurring basis | Level 2 | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	796	781
Fair value on a recurring basis | Level 2 | Certificates of deposit/time deposits
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	48	40
Fair value on a recurring basis | Level 2 | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		60
Fair value on a recurring basis | Level 2 | Asset-backed securities Automobile loan related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	537	585
Fair value on a recurring basis | Level 2 | Asset-backed securities Credit card related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	222	180
Fair value on a recurring basis | Level 2 | Asset-backed securities Equipment lease related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	88	67
Fair value on a recurring basis | Level 2 | Asset-backed securities Other asset-backed securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	68	75
Fair value on a recurring basis | Level 2 | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 2 | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		2
Fair value on a recurring basis | Level 2 | Auction rate securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 2 | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 3 | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0
Fair value on a recurring basis | Level 3 | Interest rate swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 3 | U.S. government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Certificates of deposit/time deposits
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		0
Fair value on a recurring basis | Level 3 | Asset-backed securities Automobile loan related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Asset-backed securities Credit card related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Asset-backed securities Equipment lease related
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | Asset-backed securities Other asset-backed securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	0
Fair value on a recurring basis | Level 3 | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		0
Fair value on a recurring basis | Level 3 | Auction rate securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	12	11
Fair value on a recurring basis | Level 3 | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 0	$ 0