| Assets [member] | |||||||||||||||||||||||
| Property, plant and equipment [member] | Intangible assets other than goodwill [member] | Other assets [member] | |||||||||||||||||||||
| Land and buildings [member] | Machinery [member] | Vehicles [member] | Fixtures and fittings [member] | Computer equipment [member] | Communication and network equipment [member] | Network infrastructure [member] | Bearer plants [member] | Mining assets [member] | Oil and gas assets [member] | Power generating assets [member] | Construction in progress [member] | Other property, plant and equipment [member] | |||||||||||
| Land [member] | Buildings [member] | Ships [member] | Aircraft [member] | Motor vehicles [member] | |||||||||||||||||||
| Disclosure of quantitative information about right-of-use assets [abstract] | |||||||||||||||||||||||
| Depreciation, right-of-use assets | |||||||||||||||||||||||
| Right-of-use assets | |||||||||||||||||||||||
| Right-of-use assets, revalued assets, at cost | |||||||||||||||||||||||
| Right-of-use assets, revaluation surplus | |||||||||||||||||||||||
| Right-of-use assets, increase (decrease) in revaluation surplus | |||||||||||||||||||||||
| Interest expense on lease liabilities | |||||||||||||||||||||||
| Expense relating to short-term leases for which recognition exemption has been used | |||||||||||||||||||||||
| Expense relating to leases of low-value assets for which recognition exemption has been used | |||||||||||||||||||||||
| Income from subleasing right-of-use assets | |||||||||||||||||||||||