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30. EMPLOYEE BENEFITS (Details 15) - Post-employment Healthcare Benefits [member] | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Male [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Average life expectancy of employees (in years) | 20.24 | 20.24 | 19.55
Average life expectancy in years of employees who are 40 (in years) | 42.74 | 42.74 | 41.59
Female [member] |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Average life expectancy of employees (in years) | 20.24 | 20.24 | 22.17
Average life expectancy in years of employees who are 40 (in years) | 42.74 | 42.74 | 45.30

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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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- Definition Represents the information about average life expectancy in years of employees who are 65. + References No definition available. + Details
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- Definition Represents the information about average life expectancy in years of employees who are 40. + References No definition available. + Details
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- Details
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- Details
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- Details
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