Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 515	$ 1,454
Gross Amounts of Derivative Assets Presented in the Consolidated Balance Sheet	365	256
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	81	43
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	345	229
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	79	36
Fair value on a recurring basis | Fair Value | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	2	4
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	20	27
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet		3
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	50	108
Fair value on a recurring basis | Fair Value | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	50	95
Fair value on a recurring basis | Fair Value | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	230	619
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	27	41
Fair value on a recurring basis | Fair Value | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	36
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	66	282
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	13	162
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	8	48
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	20	46
Fair value on a recurring basis | Fair Value | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities		38
Fair value on a recurring basis | Fair Value | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15	15
Fair value on a recurring basis | Fair Value | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	1	1
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	0	0
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 1 | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
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
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		38
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	0
Fair value on a recurring basis | Level 1 | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	1	1
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	345	229
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	79	36
Fair value on a recurring basis | Level 2 | Commodity price swap contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet	2	4
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	20	27
Gross Amounts of Derivative Liabilities Presented in the Consolidated Balance Sheet		3
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	50	108
Fair value on a recurring basis | Level 2 | Foreign government agency securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	50	95
Fair value on a recurring basis | Level 2 | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	230	619
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	27	41
Fair value on a recurring basis | Level 2 | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	36
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	66	282
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	13	162
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	8	48
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	20	46
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
Fair value on a recurring basis | Level 2 | U.S. municipal 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 Liabilities Presented in the Consolidated Balance Sheet	0	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
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
Fair value on a recurring basis | Level 3 | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	15	15
Fair value on a recurring basis | Level 3 | Investments
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 0	$ 0