Summary of significant accounting policies, Revenue recognition - Remaining performance obligations (Details) $ in Millions |
Dec. 31, 2025
USD ($)
|
|---|---|
| Remaining performance obligations [Abstract] | |
| Remaining performance obligations | $ 5.9 |
| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 | |
| Remaining performance obligations [Abstract] | |
| Remaining performance obligations | $ 5.5 |
| Expected timing of satisfaction, period | 12 months |
| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 | |
| Remaining performance obligations [Abstract] | |
| Remaining performance obligations | $ 0.3 |
| Expected timing of satisfaction, period | 12 months |
| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 | |
| Remaining performance obligations [Abstract] | |
| Remaining performance obligations | |
| Expected timing of satisfaction, period | 12 months |