Income taxes - Carryforwards (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Income taxes | ||
| Change in valuation allowance | $ 11.0 | $ 11.3 |
| Federal | ||
| Income taxes | ||
| Operating loss carryforwards | 213.6 | |
| Operating loss carryforward subject to expiration | 91.0 | |
| Operating loss carryforward not subject to expiration | 122.6 | |
| Tax credit carryforwards | 8.5 | |
| State | ||
| Income taxes | ||
| Operating loss carryforwards | 26.3 | |
| Tax credit carryforwards | $ 3.2 | |
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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