Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 136	$ 128	$ 265	$ 261
Income tax benefits	(38)	(42)	(86)	(84)
Total net stock-based compensation cost	97	86	178	176
Pre-tax stock-based compensation cost increase (decrease)	8		4
Pre-tax stock-based compensation cost increase related to conversion of stock-based awards of acquired entities	(7)		(13)
Stock-based compensation cost, unrecognized, related to non-vested awards	1,057		$ 1,057
Stock-based compensation cost, unrecognized, related to non-vested awards, weighted average period of recognition			2 years 8 months 12 days
Accounting Standards Update 2016-09, Stock Compensation
Stock-based compensation cost, allocation of recognized costs
Income tax benefits	4		$ (4)
Performance Share Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	7		(7)
Restricted Stock Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	8		24
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	23	23	46	44
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	98	91	189	190
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 15	$ 14	$ 29	$ 27

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

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 1
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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.

+ References

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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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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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-Publisher FASB
-Name Accounting Standards Codification
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