Debentures (Details) - Schedule of Aggregate Principal Annual Payments of Debentures $ in Thousands	Dec. 31, 2022 USD ($)
Schedule Of Aggregate Principal Annual Payments Of Debentures Abstract
2023	$ 62,180
2024	71,830
2025	86,168
2026	86,168
2027	67,606
Total	$ 373,952

Aggregate principal annual payments of debentures.

No definition available.

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The amount of repayments of bonds within next fifth and thereafter financial year.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The amount of repayments of bonds within next fourth financial year.

No definition available.

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Namespace Prefix:	forty_
Data Type:	xbrli:monetaryItemType
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The amount of repayments of bonds within seven financial year.

No definition available.

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Namespace Prefix:	forty_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The amount of repayments of bonds within next six financial year.

No definition available.

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Namespace Prefix:	forty_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of repayments of bonds within next third financial year.

No definition available.

Name:	forty_RepaymentsOfBondsWithinNextThirdFinancialYear
Namespace Prefix:	forty_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

No definition available.

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Data Type:	xbrli:stringItemType
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