v3.25.2

Note 14 - Leases (Details Textual) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
Note 14 - Leases (Details Textual) $ in Millions	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2019	May 26, 2017 ft²
Operating Lease, Cost	$ 0.2	$ 0.2	$ 0.3	$ 0.3
Operating Lease, Payments	$ 0.2	0.2	$ 0.3	$ 0.3
Operating Lease, Weighted Average Remaining Lease Term (Year)	1 year 8 months 23 days		1 year 8 months 23 days
Operating Lease, Weighted Average Discount Rate, Percent	9.95%		9.95%
Operating Lease, Liability, Noncurrent	$ 0.5		$ 0.5
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent		Other Liabilities, Noncurrent
Facilities and Office Space in Corvallis Oregon [Member]
Lessee, Operating Lease, Number of Renewal Options					2
Two Years, Option Renewal Term [Member] \| Facilities and Office Space in Corvallis Oregon [Member]
Lessee, Operating Lease, Renewal Term (Year)					2 years
Three Years, Option RenewalTerm [Member] \| Facilities and Office Space in Corvallis Oregon [Member]
Lessee, Operating Lease, Renewal Term (Year)					3 years
Increase (Decrease) in Operating Right-of-use Assets		$ 0.5
The New HQ Lease [Member] \| MacAndrews and Forbes Incorporated [Member]
Lessee, Operating Lease, Term of Contract (Year)						10 years
Area of Real Estate Property (Square Foot) \| ft²						3,200

Amount of increase (decrease) in assets for operating lease.

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- Definition

Description of terms and conditions of option to renew lessee's operating lease.

+ References

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- Definition

Area of a real estate property.

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Indicates line item in statement of financial position that includes noncurrent operating lease liability.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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SIGA TECHNOLOGIES INC 10-Q