Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 135	$ 125	$ 248	$ 242
Income tax benefits	(29)	(24)	(54)	(59)
Net stock-based compensation cost	106	102	194	183
Pre-tax stock-based compensation cost increase (decrease)	10		7
Pre-tax stock-based compensation cost increase (decrease) related to conversion of stock-based awards of acquired entities	(1)		(2)
Unrecognized compensation cost related to non-vested awards	1,000		$ 1,000
Unrecognized compensation cost related to non-vested awards, weighted average period of recognition			2 years 9 months 18 days
Restricted stock units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	13		$ 16
Performance share units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	(1)		(5)
Stock options
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	(1)		(2)
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	22	21	42	41
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	93	88	167	169
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 21	$ 16	$ 39	$ 32

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

The increase (decrease) in pre-tax share-based compensation from the corresponding period of the prior year due to conversion of share-based compensation awards previously issued by acquired entities.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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Amount, after tax, of expense for award under share-based payment arrangement.

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No definition available.

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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.

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No definition available.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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