Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
Numerator:
Net income, basic									$ 2,556	$ 3,149		$ 3,417
Net income, diluted									$ 2,556	$ 3,149		$ 3,417
Denominator:
Basic: Weighted-average common shares outstanding (in shares)	103.5	104.9	106.4	107.9	108.9	110.5	112.3	113.7	105.7	111.3		117.3
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)									2.1	2.4		2.7
Diluted: Weighted-average common shares outstanding (in shares)	105.7	107.1	108.4	110.0	111.4	112.7	114.4	116.2	107.8	113.7		120.0
Earnings Per Share, Basic:
Basic (in dollars per share)	$ 3.64	$ 8.31	$ 8.36	$ 3.86	$ 5.96	$ 9.60	$ 5.47	$ 7.26	$ 24.18	$ 28.29	[1]	$ 29.13	[1]
Earnings Per Share, Diluted:
Diluted (in dollars per share)	$ 3.57	$ 8.14	$ 8.21	$ 3.79	$ 5.83	$ 9.41	$ 5.37	$ 7.10	$ 23.71	$ 27.70	[1]	$ 28.48	[1]
Options excluded from earnings per share calculation due to their anti-dilutive effect (in shares)									0.2	0.2		0.0

[1] Certain prior period amounts have been restated. See Note 3 for more information.