XML 88 R65.htm IDEA: XBRL DOCUMENT
v3.20.4

Investment in associate - Additional information (Details) - t t in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure of associates [line items] |  |
Percentage of sales | 100.00% | 100.00%
Atlas Methanol Company Unlimited |  |
Disclosure of associates [line items] |  |
Annual methanol production facility owned (in tonnes) | 1.8 |
Ownership rate | 100.00% |
Atlas Methanol Company Unlimited | Fixed-price contracts | Methanol | 2005 through 2014 |  |
Disclosure of associates [line items] |  |
Percentage of sales | 50.00% |
Atlas Methanol Company Unlimited | Fixed-price contracts | Methanol | Late 2014 through 2019 |  |
Disclosure of associates [line items] |  |
Percentage of sales | 10.00% |
Atlas Methanol Company Unlimited |  |
Disclosure of associates [line items] |  |
Percentage of ownership interest in associates | 63.10% | 63.10%

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_DisclosureOfSignificantInvestmentsInAssociatesLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage of the entity's revenue. [Refer: Revenue] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 8 -IssueDate 2020-01-01 -Paragraph 34 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2020-en-r&anchor=para_34&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_PercentageOfEntitysRevenue
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_17_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_16_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2020-01-01 -Paragraph 21 -Subparagraph a -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_21_a_iv&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_ProportionOfOwnershipInterestInAssociate
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The proportion of ownership interest in a subsidiary attributable to the entity. [Refer: Subsidiaries [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 17 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_17_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 27 -IssueDate 2020-01-01 -Paragraph 16 -Subparagraph b -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_16_b_iii&doctype=Standard -URIDate 2020-01-01 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2020-01-01 -Paragraph 19B -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_19B_c&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_ProportionOfOwnershipInterestInSubsidiary
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Annual Mass Of Methanol Production Owned + References No definition available. + Details
Name: | mx_AnnualMassOfMethanolProductionOwned
Namespace Prefix: | mx_
Data Type: | num:massItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=mx_AtlasMethanolCompanyUnlimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TypesOfContractsAxis=ifrs-full_FixedpriceContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=mx_MethanolMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mx_TaxPeriod1Axis=mx_TaxYear2005Through2014Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mx_TaxPeriod1Axis=mx_TaxYear2014Through2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SignificantInvestmentsInAssociatesAxis=mx_AtlasMethanolCompanyUnlimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |