Name:	fsm_DebtInstrumentCashPurchasePricePercentageOfPrincipalAmountPlusAccruedInterestInEventOfFundamentalChange
Namespace Prefix:	fsm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the denomination of the principal amount of debt that is used in conversion calculations.

No definition available.

Name:	fsm_DebtInstrumentPrincipalAmountDenominationForConversionIntoCommonStock
Namespace Prefix:	fsm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of redemption.

No definition available.

Name:	fsm_DebtInstrumentRedemptionThresholdPercentageOfStockPriceTrigger
Namespace Prefix:	fsm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The price per share of the conversion feature embedded in the debt instrument.

No definition available.

Name:	fsm_IfrsDebtInstrumentConvertibleConversionPrice
Namespace Prefix:	fsm_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

No definition available.

Name:	fsm_IfrsDebtInstrumentConvertibleConversionRatio
Namespace Prefix:	fsm_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

No definition available.

Name:	fsm_IfrsDebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	fsm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

No definition available.

Name:	fsm_IfrsDebtInstrumentRedemptionPricePercentage
Namespace Prefix:	fsm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The interest rate on borrowings. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2025-01-01
-Paragraph 7
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_7&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_BorrowingsInterestRate
Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:percentItemType
Balance Type:	na
Period Type:	instant

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

Name:	ifrs-full_DisclosureOfDetailedInformationAboutBorrowingsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The cash inflow from borrowings obtained. [Refer: Borrowings]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 17
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_17_c&doctype=Standard
-URIDate 2025-03-27