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v3.20.1

19. PROPERTY, PLANT AND EQUIPMENT (Details 3) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Average annual depreciation rate | 3.13% | 3.72% | 3.14%
Hydroelectric Generation [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Average annual depreciation rate | 2.83% |  |
Thermoelectric Generation [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Average annual depreciation rate | 4.13% |  |
Wind Power Generation [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Average annual depreciation rate | 4.87% |  |
Administration [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Average annual depreciation rate | 8.29% |  |

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- Definition Average annual depreciation rate property, plant and equipment. + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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