Name:	ffh_BorrowingsNonCashChangesTransfers
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Data Type:	xbrli:monetaryItemType
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

Name:	ffh_CarryingValueOfBorrowingsRollForward
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Data Type:	xbrli:stringItemType
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Foreign Exchange Gain (Loss), Debt

No definition available.

Name:	ffh_ForeignExchangeGainLossDebt
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Face (par) amount of debt instrument at time of issuance.

No definition available.

Name:	ffh_IfrsDebtInstrumentFaceAmount
Namespace Prefix:	ffh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	ffh_NonCashChangesInCarryingValuesOfBorrowingsAbstract
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Data Type:	xbrli:stringItemType
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The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

No definition available.

Name:	ffh_NoncashOrPartNoncashAcquisitionDebtAssumed2
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of noncash consideration received for selling an asset or business through a noncash (or part noncash) transaction.

No definition available.

Name:	ffh_NoncashOrPartNoncashDivestitureAmountOfConsiderationReceived2
Namespace Prefix:	ffh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash inflow received for assuming the primary co-obligor liability for a specific debt instrument during the reporting period.

No definition available.

Name:	ffh_ProceedsFromAssumingPrimaryCoObligationForDebtInstrument
Namespace Prefix:	ffh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The net cash inflow or cash outflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

No definition available.

Name:	ffh_ProceedsFromRepaymentsOfLinesOfCredit1
Namespace Prefix:	ffh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of outstanding funds that the entity is obligated to repay.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_55&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_Borrowings
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

The cash inflow from current borrowings obtained. [Refer: Current borrowings]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 17
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_17&doctype=Standard
-URIDate 2025-03-27

Name:	ifrs-full_ProceedsFromCurrentBorrowings
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow for repayments of current borrowings. [Refer: Current borrowings]

Name:	ifrs-full_RepaymentsOfCurrentBorrowings
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Name:	ifrs-full_BorrowingsByNameAxis=ffh_BritPrimaryCoObligorOn4.73PercentUnsecuredSeniorNotesDueNovember222034Member
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_BorrowingsByNameAxis=ffh_BritPrimaryCoObligorOn5.23PercentUnsecuredSeniorNotesDueNovember232054Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_TypesOfInvestmentPropertyAxis=ffh_HoldingCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_TypesOfInvestmentPropertyAxis=ffh_InsuranceAndReinsuranceCompaniesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_BorrowingsByNameAxis=ffh_AlliedWorldUnsecuredSeniorNotes6.10PercentDueMarch152055Member
Namespace Prefix:
Data Type:	na
Balance Type:
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