Fair Value Measurements - Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	$ 885	$ 434
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	84	44
Gross Amount of Derivative Liabilities Presented in the Consolidated Balance Sheet	40	106
Fair value on a recurring basis | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	80	37
Gross Amount of Derivative Liabilities Presented in the Consolidated Balance Sheet	40	106
Fair value on a recurring basis | Interest rate contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	4	7
Fair value on a recurring basis | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	7
Fair value on a recurring basis | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	501	237
Fair value on a recurring basis | Certificates of deposit/time deposits
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	45	31
Fair value on a recurring basis | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	305	125
Fair value on a recurring basis | U.S. municipal securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	34	34
Fair value on a recurring basis | Level 1 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amount of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 1 | Interest rate contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	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 | Commercial paper
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 | U.S. treasury securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	305	125
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 2 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	80	37
Gross Amount of Derivative Liabilities Presented in the Consolidated Balance Sheet	40	106
Fair value on a recurring basis | Level 2 | Interest rate contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	4	7
Fair value on a recurring basis | Level 2 | Corporate debt securities
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	0	7
Fair value on a recurring basis | Level 2 | Commercial paper
Assets and Liabilities Measured on Recurring Basis
Available-for-sale marketable securities	501	237
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	45	31
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	0	0
Fair value on a recurring basis | Level 3 | Foreign currency forward/option contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	0	0
Gross Amount of Derivative Liabilities Presented in the Consolidated Balance Sheet	0	0
Fair value on a recurring basis | Level 3 | Interest rate contracts
Assets and Liabilities Measured on Recurring Basis
Gross Amount of Derivative Assets Presented in the Consolidated Balance Sheet	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 | Commercial paper
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 | 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	$ 34	$ 34