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Restructuring - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]
Cumulative costs since program inception	$ 2,100
Estimate of cumulative pre tax costs that will result in cash outlays	70.00%
Estimate of cumulative pre tax costs that will be noncash	30.00%
Expected restructuring and related cost	$ 3,000
Total pretax restructuring costs	$ 335	$ 168
Forecast
Restructuring Cost and Reserve [Line Items]
Expected restructuring and related cost			$ 700

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Estimate of cumulative pre tax costs that will be noncash.

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Estimate of cumulative pre tax costs that will result in cash outlays (primarily from employee separation expense).

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- Definition

Amount of costs incurred to date for the specified restructuring cost.

+ References

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Amount expected to be recognized in earnings for the specified restructuring cost.

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