XML 144 R107.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Commitments and contingencies - Minimum purchase contract commitment (Details) - Take-or-pay purchase contracts $ in Thousands | Dec. 31, 2017 USD ($)
--- | ---
2018 |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | $ 473,927
2019 |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | 371,167
2020 |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | 306,400
2021 |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | 308,338
2022 |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | 245,989
Thereafter |
Disclosure of contingent liabilities [line items] |
Minimum estimated commitment | $ 1,300,609

X
- 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
Name: | ifrs-full_DisclosureOfContingentLiabilitiesLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of the estimated financial effect of contingent liabilities. [Refer: Contingent liabilities [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2017-01-01 -Paragraph 86 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_86_a&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_EstimatedFinancialEffectOfContingentLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ifrs-full_ClassesOfContingentLiabilitiesAxis=mx_PurchaseCommitment1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_NotLaterThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanOneYearAndNotLaterThanTwoYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanTwoYearsAndNotLaterThanThreeYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanThreeYearsAndNotLaterThanFourYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanFourYearsAndNotLaterThanFiveYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_MaturityAxis=ifrs-full_LaterThanFiveYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |