XML 110 R82.htm IDEA: XBRL DOCUMENT v3.20.4
Significant Accounting Policies (Details)
 12 Months Ended
Dec. 31, 2020
Hydro generation | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 1 year
Hydro generation | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 52 years
Wind generation | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 1 year
Wind generation | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 29 years
Gas generation | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 1 year
Gas generation | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 17 years
Coal generation | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 1 year
Coal generation | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 29 years
Mining property and equipment | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 1 year
Mining property and equipment | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 9 years
Capital spares and other | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 2 years
Capital spares and other | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 52 years
Facilities | Minimum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 30 years
Facilities | Maximum  
Disclosure of detailed information about property, plant and equipment [line items]  
Useful life measured as period of time, property, plant and equipment 60 years
Software | Minimum  
Disclosure of detailed information about intangible assets [line items]  
Useful life measured as period of time, intangible assets other than goodwill 2 years
Software | Maximum  
Disclosure of detailed information about intangible assets [line items]  
Useful life measured as period of time, intangible assets other than goodwill 7 years
Power sale contracts | Minimum  
Disclosure of detailed information about intangible assets [line items]  
Useful life measured as period of time, intangible assets other than goodwill 1 year
Power sale contracts | Maximum  
Disclosure of detailed information about intangible assets [line items]  
Useful life measured as period of time, intangible assets other than goodwill 20 years