Land use right - Summary of Quantitative Information About Land Use Right (Details) - CNY (¥) ¥ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| Disclosure Of Quantitative Information About Land Use Right [Line Items] | |||
| Beginning balance | ¥ 2,364 | ||
| Additions | 972 | ¥ 684 | |
| Amortization charge | (1,218) | (799) | ¥ (781) |
| Ending balance | 2,290 | 2,364 | |
| Land [Member] | |||
| Disclosure Of Quantitative Information About Land Use Right [Line Items] | |||
| Beginning balance | 2,364 | 2,437 | |
| Amortization charge | (74) | (73) | |
| Ending balance | ¥ 2,290 | ¥ 2,364 | ¥ 2,437 |