Basis of Presentation - Out of Period Correction (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Out-of-period corrections
Other comprehensive loss, net of tax	$ (898)	$ (312)
Correction related to defined benefit plans
Out-of-period corrections
Other comprehensive loss, net of tax		$ 29

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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