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20. INTANGIBLE ASSETS (Details 3) | 12 Months Ended
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Dec. 31, 2019
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 4.01%
Hydroelectric Generation [Member] |
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 19.74%
Wind Power Generation [Member] |
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 16.90%
Administration [Member] |
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 16.03%
Distribution [Member] |
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 3.88%
Gas [Member] |
Disclosure of detailed information about intangible assets [line items] |
Annual average amortization rate | 2.87%

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- Definition Amount refers to useful lives or amortisation rates intangible assets other than goodwill. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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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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- Details
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Namespace Prefix: |
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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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Period Type: |

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- Details
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Balance Type: |
Period Type: |