Income taxes - Elements of Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred income tax assets (liabilities)
- Depreciation & amortization	$ (7,424)	$ (4,899)
- Reserves for doubtful accounts	324	163
- Inventory reserve	1,408	2,083
- Non qualified stock options	1,219	965
- Net operating losses	11,963	11,016
- Amt credit	0	47
- Deferred interest	10,114	8,351
- Deferred bonus	74	0
- Valuation allowance	(19,033)	(18,918)	$ (11,300)
Total	$ (1,355)	$ (1,192)

Amount of deferred tax assets deferred income.

No definition available.

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- Definition

Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Depreciation And Amortization.

+ References

No definition available.

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- Definition

It represents Deferred Tax Assets Tax Deferred Expense Reserves And Non Qualified Stock Options.

+ References

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

+ References

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- References

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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.

+ References

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- Definition

Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from reserves, classified as other.

+ References

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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.

+ References

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- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

+ References

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