Summary of significant accounting policies - Useful lives property, plant and equipment and right-of-use lease assets (Details) |
12 Months Ended |
|---|---|
Dec. 31, 2023 | |
| Network assets | Minimum | |
| Property, plant and equipment | |
| Useful lives | 3 years |
| Network assets | Maximum | |
| Property, plant and equipment | |
| Useful lives | 7 years |
| Buildings and leasehold improvements | Minimum | |
| Property, plant and equipment | |
| Useful lives | 5 years |
| Buildings and leasehold improvements | Maximum | |
| Property, plant and equipment | |
| Useful lives | 20 years |
| Computer equipment, furniture, and other | Minimum | |
| Property, plant and equipment | |
| Useful lives | 3 years |
| Computer equipment, furniture, and other | Maximum | |
| Property, plant and equipment | |
| Useful lives | 7 years |
| Right-of-use lease assets | Minimum | |
| Property, plant and equipment | |
| Useful lives | 3 years |
| Right-of-use lease assets | Maximum | |
| Property, plant and equipment | |
| Useful lives | 20 years |