v3.26.3
Critical accounting estimates and judgments (Details) - USD ($)
$ / shares in Units, $ in Millions
Sep. 30, 2026
Jun. 30, 2026
Dec. 31, 2025
Sep. 30, 2025
Jun. 30, 2025
Dec. 31, 2024
Critical accounting estimates and assumptions [Line Items]            
Cash and cash equivalents $ 1,836.3   $ 825.7      
Cash and cash equivalents if different from statement of financial position 1,836.3 $ 1,093.4 853.3 $ 651.5 $ 533.1 $ 578.0
Cash and cash equivalents held for sale     27.6      
Deferred income tax liabilities 42.2   40.4      
Deferred income tax assets $ 86.1   $ 65.1      
MTN Group            
Critical accounting estimates and assumptions [Line Items]            
Price per share of entity's shares in merger agreement $ 8.5