Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 220	$ 129	$ 468	$ 371
Income tax benefits	(50)	(29)	(104)	(88)
Net stock-based compensation cost	170	100	364	283
Pre-tax stock-based compensation cost increase (decrease)	91		98
Pre-tax stock-based compensation cost increase (decrease) related to conversion of stock-based awards of acquired entities	79		79
Unrecognized compensation cost related to non-vested awards	1,400		$ 1,400
Unrecognized compensation cost related to non-vested awards, weighted average period of recognition			2 years 6 months
Restricted stock units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	10		$ 25
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	29	19	71	60
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	147	95	313	264
R&D expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 44	$ 15	$ 84	$ 47

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
-Topic 718
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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ 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

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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