XML 106 R83.htm IDEA: XBRL DOCUMENT
v3.20.4

Finance costs (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Borrowing costs [abstract] |  |
Finance costs before capitalized interest | $ 182,841,000 | $ 127,282,000
Less capitalized interest | (18,004,000) | (2,856,000)
Finance costs | 164,837,000 | 124,426,000
Disclosure of detailed information about borrowings [line items] |  |
Long-term debt | 2,363,372,000 | $ 1,768,853,000
Unsecured notes due March 2020 |  |
Disclosure of detailed information about borrowings [line items] |  |
Make-whole interest charge on borrowings | 15,400,000 |
Long-term debt | $ 250,000,000 |

X
- References No definition available. + Details
Name: | ifrs-full_BorrowingCostsAbstract
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_Borrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition The amount of costs associated with financing activities of the entity. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 82 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_82_b&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_FinanceCosts
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of interest expense on borrowings. [Refer: Interest expense; Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_InterestExpenseOnBorrowings
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Capitalized Interest + References No definition available. + Details
Name: | mx_CapitalizedInterest
Namespace Prefix: | mx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Finance Costs Before Capitalized Interest + References No definition available. + Details
Name: | mx_FinanceCostsBeforeCapitalizedInterest
Namespace Prefix: | mx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | ifrs-full_BorrowingsByNameAxis=mx_UnsecuredDebtDueMarch2020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |