Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 113	$ 116
Income tax benefits	(25)	(35)
Net stock-based compensation cost	88	81
Pre-tax stock-based compensation cost increase (decrease)	(3)
Unrecognized compensation cost related to non-vested awards	$ 671
Unrecognized compensation cost related to non-vested awards, weighted average period of recognition	2 years 6 months
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 20	20
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	74	81
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 19	$ 16

Represents the change in the pre-tax stock-based compensation cost from the corresponding period in the prior year.

No definition available.

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- Definition

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.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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