Shareholders' equity Schedule of Dividends Declared (Details)	12 Months Ended
	Dec. 31, 2022 SFr / shares	Dec. 31, 2022 $ / shares	Dec. 31, 2021 SFr / shares	Dec. 31, 2021 $ / shares	Dec. 31, 2020 SFr / shares	Dec. 31, 2020 $ / shares
Switzerland, Francs
Dividends Declared [Line Items]
Total dividend distributions per common share | SFr / shares	SFr 3.11		SFr 2.88		SFr 2.89
United States of America, Dollars
Dividends Declared [Line Items]
Total dividend distributions per common share | $ / shares		$ 3.29		$ 3.18		$ 3.09