Income Taxes - Significant Components of Current and Non-current Deferred Taxes (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Inventory	$ 8,882	$ 7,144
Accrued expenses	2,331	2,330
Deferred compensation	6,714	5,660
Stock-based compensation	1,971	2,451
Uncertain tax positions related to state taxes and related interest	149	241
Pensions	8,554	7,074
Foreign losses	2,590	2,925
State losses and credit carry-forwards	5,509	3,995
Federal loss and research carry-forwards	17,323	12,171
Lease liabilities	1,588	2,496
Capitalized research and development expenditures	11,832	22,230
Valuation allowance	(45,818)	(48,616)
Total Deferred Tax Assets	21,625	20,101
Property, plant and equipment	(4,546)	(2,815)
Intellectual property	(4,375)	(5,337)
Right of use lease assets	(1,585)	(2,496)
Investments	(1,250)	(1,892)
Total Deferred Tax Liabilities	(11,756)	(12,540)
Net Deferred Tax Assets	$ 9,869	$ 7,561

Deferred tax assets lease liabilities.

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Amount before allocation of valuation allowances of deferred tax assets attributable to uncertain tax positions related to state taxes and related interest.

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Deferred tax liabilities right of use lease assets.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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

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

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs.

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

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

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

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains in other comprehensive income.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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