Supplemental financial information - Amounts Reclassified out of AOCI (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense), net (OI&E)		$ 123	$ 80
Provision for income taxes		(188)	(238)
Net income		1,105	1,708
Reclassification out of Accumulated Other Comprehensive Income | Net actuarial losses of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense), net (OI&E)	[1]	3	4
Provision for income taxes		(1)	(1)
Net income		$ 2	$ 3

[1] Detailed in Note 5