XML 65 R66.htm IDEA: XBRL DOCUMENT
v3.20.1

Property, plant and equipment - Owned Assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | $ 2,857,266 |
Value at end of period | 2,940,777 | $ 2,857,266
Buildings, plant installations and machinery |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 2,650,407 |
Value at end of period | 2,572,455 | 2,650,407
Plants under construction |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 0 |
Value at end of period | 155,871 | 0
Ocean going vessels |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 134,993 |
Value at end of period | 176,499 | 134,993
Other |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 71,866 |
Value at end of period | 35,952 | 71,866
Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 5,070,619 | 4,924,417
Additions | 330,636 | 279,070
Disposals and other | (101,454) | (132,868)
Transfers | 0 |
Value at end of period | 5,299,801 | 5,070,619
Cost | Buildings, plant installations and machinery |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 4,698,142 | 4,648,924
Additions | 150,570 | 180,437
Disposals and other | (61,197) | (131,219)
Transfers | 0 |
Value at end of period | 4,787,515 | 4,698,142
Cost | Plants under construction |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 0 | 0
Additions | 118,249 | 0
Disposals and other | 0 | 0
Transfers | 37,622 |
Value at end of period | 155,871 | 0
Cost | Ocean going vessels |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 183,419 | 144,423
Additions | 57,479 | 40,284
Disposals and other | (38,951) | (1,288)
Transfers | 0 |
Value at end of period | 201,947 | 183,419
Cost | Other |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 189,058 | 131,070
Additions | 4,338 | 58,349
Disposals and other | (1,306) | (361)
Transfers | (37,622) |
Value at end of period | 154,468 | 189,058
Accumulated depreciation |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | (2,213,353) |
Disposals and other | (96,386) | (126,474)
Depreciation | 242,057 | 231,890
Value at end of period | (2,359,024) | (2,213,353)
Accumulated depreciation | Buildings, plant installations and machinery |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | (2,047,735) |
Disposals and other | (63,169) | (124,920)
Depreciation | 230,494 | 216,338
Value at end of period | (2,215,060) | (2,047,735)
Accumulated depreciation | Plants under construction |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | 0 |
Disposals and other | 0 | 0
Depreciation | 0 | 0
Value at end of period | 0 | 0
Accumulated depreciation | Ocean going vessels |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | (48,426) |
Disposals and other | (31,620) | (1,194)
Depreciation | 8,642 | 9,193
Value at end of period | (25,448) | (48,426)
Accumulated depreciation | Other |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Value at beginning of period | (117,192) |
Disposals and other | (1,597) | (360)
Depreciation | 2,921 | 6,359
Value at end of period | $ (118,516) | $ (117,192)

X
- Definition The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e_i&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -Clause vii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e_vii&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 75 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_75_a&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DepreciationPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The decrease in property, plant and equipment resulting from disposals. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e_ii&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DisposalsPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The increase (decrease) in property, plant and equipment resulting from transfers. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_IncreaseDecreaseThroughTransfersPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2019-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_54_a&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_PropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=mx_BuildingsPlantInstallationsAndMachineryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ifrs-full_ConstructionInProgressMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ifrs-full_ShipsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=ifrs-full_OtherPropertyPlantAndEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_GrossCarryingAmountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_AccumulatedDepreciationAndAmortisationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |