v3.26.1
Segment reporting - Summarized financial information (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Geographical information        
Revenues from external customers $ 428.6 $ 388.2 [1] $ 844.0 $ 780.3 [1]
Discontinued operations        
Geographical information        
Revenues from external customers 42.4 45.1 94.2 92.6
Aggregate continuing and discontinuing operations        
Geographical information        
Segment Adjusted EBITDA 270.0 277.3 567.8 563.7
Nigeria        
Geographical information        
Revenues from external customers 298.3 260.4 583.2 531.7
Nigeria | Aggregate continuing and discontinuing operations        
Geographical information        
Revenues from external customers 298.3 260.4 583.2 531.7
Segment Adjusted EBITDA 166.5 170.7 349.0 349.8
SSA        
Geographical information        
Revenues from external customers 130.3 127.8 260.8 248.6
SSA | Aggregate continuing and discontinuing operations        
Geographical information        
Revenues from external customers 130.3 127.8 260.8 248.6
Segment Adjusted EBITDA 70.8 73.1 148.4 144.8
Latam | Discontinued operations        
Geographical information        
Revenues from external customers 42.4 45.1 94.2 92.6
Latam | Aggregate continuing and discontinuing operations        
Geographical information        
Revenues from external customers 42.4 45.1 94.2 92.6
Segment Adjusted EBITDA $ 32.7 $ 33.5 $ 70.4 $ 69.1
[1] The results for the three and six months ended June 30, 2025 have been re-presented to reflect that the results of the Latam segment is now reported as a discontinued operation. See note 21.1 for more information