Incentive Stock Programs - Options (Details) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) $ / shares shares
Incentive Stock Program
Total unrecognized compensation cost	$ 552
Total unrecognized compensation cost, recognition period	3 years
Stock options
Incentive Stock Program
Stock options outstanding, number of shares \| shares	29,594,797
Exercisable options, number of shares \| shares	22,674,416
Stock options outstanding, weighted-average remaining life	5 years 9 months 18 days
Exercisable options, weighted-average remaining life	4 years 10 months 24 days
Stock options outstanding, weighted-average exercise price (in dollars per share) \| $ / shares	$ 63.08
Exercisable options, weighted-average exercise price (in dollars per share) \| $ / shares	$ 51.79
Aggregate intrinsic value of options outstanding	$ 1,645
Aggregate intrinsic value of options exercisable	$ 1,504

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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