Shareholders' equity Dividends Declared (Details)	3 Months Ended
Mar. 31, 2025 $ / shares	Mar. 31, 2025 SFr / shares	Mar. 31, 2024 $ / shares	Mar. 31, 2024 SFr / shares
Equity, Class of Treasury Stock [Line Items]
Common Stock, Dividends, Per Share, Declared \| (per share)	$ 0.91	SFr 0.81	$ 0.86	SFr 0.75

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration