Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 234	$ 198
Income tax benefits	(57)	(48)
Net stock-based compensation cost	177	149
Pre-tax stock-based compensation cost increase (decrease)	36
Unrecognized compensation cost related to non-vested awards	$ 1,500
Unrecognized compensation cost related to non-vested awards, weighted average period of recognition	2 years 7 months 6 days
Performance Share Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	$ 3
Restricted Stock Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	28
Stock Options
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	5
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	40	34
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	136	115
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 57	$ 49

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

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

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

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