Name:	siga_ShareBasedCompensationArragementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageExcercisePrice
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Amount of difference between fair value of the underlying equity instrument for the issuance and exercise price of vested portions of equity instruments outstanding and currently exercisable.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The weighted-average remaining life in years, for excercisable equity instruments other than options.

No definition available.

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Amount of difference between fair value of the underlying equity instruments reserved for issuance and exercise price of equity instruments outstanding.

No definition available.

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Namespace Prefix:	siga_
Data Type:	xbrli:monetaryItemType
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The weighted-average remaining life in years, for equity instruments other than options vested and expected to vest.

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageRemainingLife
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Data Type:	xbrli:durationItemType
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Period Type:	duration

The number of shares into which fully or partially vested, other than stock (or unit) option plans outstanding as of the balance sheet date can be currently converted under the option plan.

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThenOptionsExercisableNumber
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted-average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

No definition available.

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Namespace Prefix:	siga_
Data Type:	num:perShareItemType
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Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Weighted Average Exercise Price [Roll Forward]

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePriceRollForward
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of canceled and expired options under the stock option plan.

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsCanceledExpiredWeightedAverageExcercisePrice
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Data Type:	num:perShareItemType
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Period Type:	duration

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of exercised options under the stock option plan.

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExcercisedWeightedAverageExcercisePrice
Namespace Prefix:	siga_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of granted options under the stock option plan.

No definition available.

Name:	siga_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedWeightedAverageExcercisePrice
Namespace Prefix:	siga_
Data Type:	num:perShareItemType
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The number of exercises made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract
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Data Type:	xbrli:stringItemType
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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Period Type:	duration

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Per share weighted average intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Data Type:	num:perShareItemType
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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.

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Data Type:	xbrli:stringItemType
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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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Period Type:	instant

- References

No definition available.

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901