Segment reporting - Summarized financial information (Details) $ in Millions |
3 Months Ended | ||||
|---|---|---|---|---|---|
|
Mar. 31, 2026
USD ($)
segment
|
Mar. 31, 2025
USD ($)
|
||||
| Disclosure of operating segments [line items] | |||||
| Number of operating segments | segment | 3 | ||||
| Revenues from external customers | $ 415.4 | $ 392.1 | [1] | ||
| Elimination of intersegment amounts | |||||
| Disclosure of operating segments [line items] | |||||
| Revenues from external customers | 0.0 | ||||
| Nigeria | |||||
| Disclosure of operating segments [line items] | |||||
| Revenues from external customers | 285.0 | 271.4 | |||
| SSA | |||||
| Disclosure of operating segments [line items] | |||||
| Revenues from external customers | $ 130.4 | $ 120.7 | |||
| |||||