XML 49 R72.htm IDEA: XBRL DOCUMENT
v3.20.1

Significant Accounting Policies (Narrative) (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2019
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Lease liabilities | $ 23,879,000 | $ 8,766,000 |  | $ 16,083,000
Right-of-use assets | $ 7,316 |  |  |
Weighted average lessee's incremental borrowing rate applied to lease liabilities recognised at date of initial application of IFRS 16 |  |  |  | 5.32%
Machinery and Equipment [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Depreciation method, property, plant and equipment | Straight line |  |  |
Useful lives or depreciation rates, property, plant and equipment | 3-12 years |  |  |
Mineral Properties [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Depreciation method, property, plant and equipment | Declining balance |  |  |
San Jose M&I Property [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Conversion factors related to inferred resources | 90.00% | 90.00% |  |
Percentage of inferred resources | 29.00% | 21.00% | 23.00% |
Caylloma M&I Property [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Conversion factors related to inferred resources | 80.00% | 80.00% |  |
Percentage of inferred resources | 45.00% | 48.00% | 60.00% |
Performance Share Units | Bottom of range [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Vesting tranche percentage sharebased arrangements | 50.00% |  |  |
Performance Share Units | Top of range [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Vesting tranche percentage sharebased arrangements | 200.00% |  |  |
Performance Share Units | Vesting Tranche One Period [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Vesting tranche percentage sharebased arrangements | 20.00% |  |  |
Performance Share Units | Vesting Tranche Two Period [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Vesting tranche percentage sharebased arrangements | 30.00% |  |  |
Performance Share Units | Vesting Tranche Three Period [member] |  |  |  |
Disclosure Of Significant Accounting Policies [line items] |  |  |  |
Vesting tranche percentage sharebased arrangements | 50.00% |  |  |

X
- Definition Conversion factors related to inferred resources. + References No definition available. + Details
Name: | fsm_ConversionFactorsRelatedToInferredResources
Namespace Prefix: | fsm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure Of Significant Accounting Policies [line items]. + References No definition available. + Details
Name: | fsm_DisclosureOfSignificantAccountingPoliciesLineItems
Namespace Prefix: | fsm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of inferred resources. + References No definition available. + Details
Name: | fsm_PercentageOfInferredResources
Namespace Prefix: | fsm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Vesting tranche percentage sharebased arrangements. + References No definition available. + Details
Name: | fsm_VestingTranchePercentageSharebasedArrangements
Namespace Prefix: | fsm_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The depreciation method used for property, plant and equipment. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 73 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_73_b&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_DepreciationMethodPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2019-01-01 -Name IFRS -Number 16 -IssueDate 2018-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=16&date=2018-03-01&anchor=para_47_b&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_LeaseLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2019-01-01 -Name IFRS -Number 16 -IssueDate 2018-01-01 -Paragraph 53 -Subparagraph j -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=16&date=2018-03-01&anchor=para_53_j&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_RightofuseAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The useful lives or depreciation rates used for property, plant and equipment. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 73 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_73_c&doctype=Standard -URIDate 2018-03-16 + Details
Name: | ifrs-full_UsefulLivesOrDepreciationRatesPropertyPlantAndEquipment
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average lessee's incremental borrowing rate applied to lease liabilities recognised in the statement of financial position at the date of initial application of IFRS 16. The incremental borrowing rate is the rate of interest that a lessee would have to pay to borrow over a similar term, and with a similar security, the funds necessary to obtain an asset of a similar value to the right-of-use asset in a similar economic environment. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2019-01-01 -Name IFRS -Number 16 -IssueDate 2018-01-01 -Paragraph C12 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=16&date=2018-03-01&anchor=para_C12_a&doctype=Appendix&seq=3 -URIDate 2018-03-16 + Details
Name: | ifrs-full_WeightedAverageLesseesIncrementalBorrowingRateAppliedToLeaseLiabilitiesRecognisedAtDateOfInitialApplicationOfIFRS16
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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

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

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

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

X
- Details
Name: | ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=fsm_PerformanceShareUnitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fsm_VestingTrancheAxis=fsm_VestingTrancheOnePeriodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fsm_VestingTrancheAxis=fsm_VestingTrancheTwoPeriodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fsm_VestingTrancheAxis=fsm_VestingTrancheThreePeriodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |