Pension and other postretirement benefits - Schedule of Weighted Average Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
OPEB Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.08%	2.59%	2.18%
Rate of compensation increase	2.80%	2.22%	2.37%
United States | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.20%	2.70%	2.25%
Rate of compensation increase		3.50%	3.50%
Expected long‐term rate of return on plan assets	5.50%	5.50%	5.50%
Non-U.S. | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.13%	1.54%	1.23%
Rate of compensation increase	3.22%	2.74%	2.39%
Expected long‐term rate of return on plan assets	4.04%	2.54%	2.51%
Interest crediting rates	1.50%	2.25%	1.25%