INCOME TAXES - Significant components of deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Warranty costs	$ 1,254	$ 1,021
Stock-based compensation	866	780
Pension	3,099	3,196
State NOL's	221	283
Capitalized research and development	1,300
All others, net	789	589
Total deferred tax assets	7,529	5,869
Deferred tax liabilities:
Depreciation and amortization expense	(1,092)	(1,033)
Basis differences in joint venture	(410)	(444)
Net deferred tax assets	$ 6,027	$ 4,392

This element represents warranty costs of deferred tax assets.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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- Definition

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

+ References

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- References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32632-109319

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32621-109319

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

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- References

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Amount of deferred tax liability attributable to taxable temporary differences from investments in unconsolidated subsidiaries and investments in other affiliates which are not controlled nor consolidated.

+ References

+ Details

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- Definition

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

+ References

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