Share-based compensation (Weighted Average Assumptions for Option Grants) (Details) - Options	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	1.70%	1.70%	1.90%
Expected volatility	23.00%	20.10%	26.00%
Risk-free interest rate	4.10%	1.90%	1.00%
Expected life	5 years 8 months 12 days	5 years 9 months 18 days	5 years 9 months 18 days