| Analysis of income and expense [abstract] | ||
| Revenue [abstract] | ||
| Revenue from sale of goods | ||
| Revenue from rendering of services | ||
| Revenue from construction contracts | ||
| Interest income | ||
| Dividend income | ||
| Income from government grants | ||
| Other revenue | ||
| Revenue | ||
| Classes of employee benefits expense [abstract] | ||
| Wages and salaries | ||
| Social security contributions | ||
| Other short-term employee benefits | ||
| Post-employment benefit expense, defined contribution plans | ||
| Post-employment benefit expense, defined benefit plans | ||
| Termination benefits expense | ||
| Other long-term employee benefits | ||
| Other employee expense | ||
| Employee benefits expense | ||