Income taxes - Schedule of Deferred Tax Assets (Details) - USD ($) |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| Net operating loss carryforwards | $ 7,206,000 | $ 7,429,000 |
| R&D and ITC credit carryforwards | 244,000 | 203,000 |
| Accrued expenses and other | 1,140,000 | 879,000 |
| Accounts receivable | 7,000 | 6,000 |
| Inventory | 73,000 | 73,000 |
| Property, plant and equipment | 568,000 | 801,000 |
| Deferred tax assets | 9,238,000 | 9,391,000 |
| Valuation allowance | (9,238,000) | (9,391,000) |
| Deferred tax assets, net | $ 0 | $ 0 |
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- Definition Deferred Tax Asset, Tax Deferred Expense, Reserves And Accruals Accrued Liabilities And Other No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment. No definition available.
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- Definition Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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