Stock-Based Compensation - Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Amounts recognized in the financial statements
Stock-based compensation programs expense	$ 130	$ 159
Income tax benefits	(80)	(98)
Stock-based compensation expenses (benefits), net of tax	50	61
Cost of sales
Amounts recognized in the financial statements
Stock-based compensation programs expense	22	23
Selling, general and administrative expenses
Amounts recognized in the financial statements
Stock-based compensation programs expense	82	109
Research, development and related expenses
Amounts recognized in the financial statements
Stock-based compensation programs expense	$ 26	$ 27

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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