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Income taxes.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes (Details Textual) - USD ($)	12 Months Ended
Income Taxes (Details Textual) - USD ($)	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2018
Income Taxes [Line Items]
Valuation allowance	$ 143,528,000	$ 138,044,000
Valuation allowance change	$ 5,500,000	29,200,000
Maximum percentage of likelihood of uncertain tax position recognized to be sustained	50.00%
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$ 0	$ 0	$ 0
Net Operating Loss and Research and Development Credit Carryforwards Limitations On Cumulative Change In Ownership Minimum Percentage	50.00%
Net Operating Loss and Research and Development Credit Carryforwards Limitations on Cumulative Change In Ownership Period	3 years
Orphan Drug Credit [Member]
Income Taxes [Line Items]
Credit Carryforward Amount	$ 8,900,000
Credit Carryforward Expiration Year	2042
Minimum [Member]
Income Taxes [Line Items]
Foreign jurisdictions filing tax returns period	4 years
Maximum [Member]
Income Taxes [Line Items]
Foreign jurisdictions filing tax returns period	5 years
Federal [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 115,500,000
Federal [Member] \| Research Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Credit Carryforward Amount	$ 18,100,000
Credit Carryforward Expiration Year	2037
State [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 203,100,000			$ 700,000
Operating Loss Carryforwards Expiration Year	2039
Credit Carryforward Amount	$ 1,000,000
Credit Carryforward Expiration Year	2037
State [Member] \| Research Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Credit Carryforward Amount	$ 12,500,000