Profit per share (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023		Dec. 31, 2022	Dec. 31, 2021	Aug. 01, 2022	May 31, 2022	Jul. 01, 2018
Stock repurchase
Common shares under SARs and stock options not included in the computation of diluted earnings per share (in shares)	800,000		2,000,000	1,100,000
Common shares repurchased (in shares)	19,466,020		21,882,818	12,987,299
Common shares repurchased	$ 4,675	[1]	$ 4,230	$ 2,668
2018 Authorization Program
Stock repurchase
Authorized amount							$ 10,000
Remaining authorized repurchase					$ 70
2022 Authorization Program
Stock repurchase
Authorized amount						$ 15,000
Remaining authorized repurchase	$ 7,800

[1] See Note 16 regarding shares repurchased.