Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 213	$ 189
Income tax benefits	(52)	(45)
Net stock-based compensation cost	161	144
Pre-tax stock-based compensation cost increase (decrease)	24
Unrecognized compensation cost related to non-vested awards	$ 1,200
Unrecognized compensation cost related to non-vested awards, weighted average period of recognition	2 years 1 month 6 days
Performance Share Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	$ 16
Restricted Stock Units
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost increase (decrease)	8
Cost
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	41	27
SG&A expense
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	123	117
Research, development and engineering
Stock-based compensation cost, allocation of recognized costs
Pre-tax stock-based compensation cost	$ 49	$ 45

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

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