SUPPLEMENTARY FINANCIAL STATEMENT INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Government institutions	$ 12,830forty_DueToGovernmentInstitutions	$ 13,068forty_DueToGovernmentInstitutions
Customer advances	187us-gaap_CustomerAdvancesCurrent	2,601us-gaap_CustomerAdvancesCurrent
Deferred taxes (Note 15e)	1,375us-gaap_DeferredTaxLiabilitiesCurrent	2,567us-gaap_DeferredTaxLiabilitiesCurrent
Accrued royalties to the OCS (Note 13f)	788	0
Accrued expenses and other current liabilities	9,733	4,617
Total	$ 24,913us-gaap_AccountsPayableOtherCurrent	$ 22,853us-gaap_AccountsPayableOtherCurrent

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Carrying value as of the balance sheet date of obligations incurred and payable, which are not elsewhere specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of obligations incurred and payable, pertaining to costs that are statutory in nature, incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include, but not limited to, taxes, interest, rent and utilities. Also includes the aggregate carrying amount of liabilities not separately disclosed.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties.

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The current portion of prepayments received from customers for goods or services to be provided in the future.

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Amount of deferred tax liability attributable to taxable temporary differences, net of deferred tax asset attributable to deductible temporary differences and carryforwards net of valuation allowances expected to be realized or consumed within one year or operating cycle, if longer.

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