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Share-Based Payments (Narrative) (Details) - USD ($) shares in Millions, $ 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]
Number of authorized shares of common stock for share-based payment arrangements (in shares)	128
Total unrecognized compensation cost related to nonvested share-based payment arrangements granted	$ 547
Weighted-average period to recognize the cost (years) - nonvested units	1 year 8 months 8 days
Total fair value of shares vested during the year - nonvested units	$ 783	$ 608	$ 471
Cash proceeds from exercise of stock options	$ 2	$ 11	$ 21
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock and stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock and stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Other nonvested stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Other nonvested stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Other nonvested stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years