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v3.20.4

Significant accounting policies - Property plant and equipment (Details) - Buildings, plant installations and machinery | 12 Months Ended
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Dec. 31, 2020
Bottom of range |
Disclosure of detailed information about property, plant and equipment [line items] |
Estimated useful lives | 10 years
Top of range |
Disclosure of detailed information about property, plant and equipment [line items] |
Estimated useful lives | 25 years

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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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Period Type: | duration

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- Definition Useful lives or depreciation rates, property, plant and equipment, period + References No definition available. + Details
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Namespace Prefix: | mx_
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Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |