Share-Based Compensation Plans - Share-based compensation expense recognized in continuing operations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 397	$ 449	$ 312
Tax benefit	83	87	61
Share-based compensation expense, net of tax	314	362	251
Employee share purchase plans and other
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	12	56	10
Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	251	204	186
Performance share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 134	$ 189	$ 116

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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