Note 13 - Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($) |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Inventories | $ 179,171 | $ 164,768 |
| Bad debts | 5,009 | 4,659 |
| Accrued liabilities | 48,812 | 279,508 |
| Prepaid expense | (92,571) | (116,524) |
| Depreciation and amortization | (2,757,740) | (2,798,040) |
| Research and development and other credit carryforwards | 451,247 | 556,387 |
| Right of use lease accounting | 47,351 | |
| Right of use lease accounting | (19,600) | |
| Directors stock option plan | 161,212 | 163,427 |
| Total deferred tax liability | (1,957,509) | (1,765,415) |
| Valuation allowance | (47,319) | (47,319) |
| Reserve for uncertain tax positions | (425,000) | (395,000) |
| Total reserves & allowances | (472,319) | (442,319) |
| Net deferred tax liability, net of reserves | $ (2,429,828) | $ (2,207,734) |
| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from right of use assets. No definition available.
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| X | ||||||||||
- Definition Amount of valuation allowance, not including reserves, of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as current. No definition available.
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| X | ||||||||||
- Definition Amount of reserves included in the valuation allowance of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as current. No definition available.
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee compensation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- 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://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- 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/disclosureRef
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| X | ||||||||||
- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses. No definition available.
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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