Stock-Based Compensation - Schedule of Options Exercised, Cash Received, and Related Tax Benefits (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Stock options exercised (in shares)	313,358	55,155	998,996	677,072
Cash received upon exercise	$ 27	$ 3	$ 82	$ 47
Related tax benefit realized	$ 8	$ 1	$ 24	$ 16

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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