Incentive Stock Program - Expense (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Incentive Stock Programs
Total non-cash compensation expense charged against income	$ 640	$ 546	$ 519
Tax benefit recognized in total non-cash compensation expense	$ 267	$ 200	$ 197

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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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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