Share-Based Compensation Plans - Share-based compensation expense recognized in continuing operations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 449	$ 312	$ 317
Tax benefit	87	61	66
Share-based compensation expense, net of tax	362	251	251
Employee share purchase plans and other
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	56	10	9
Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	204	186	198
Performance share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 189	$ 116	$ 110

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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