Note 13 - Income Taxes - Components of Deferred Income Tax Assets and (Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Jun. 30, 2024
Uncertain tax positions	$ 241	$ 241
Reserves against current assets	2,384	1,408
Accrued expenses	3,962	3,029
Deferred compensation	2,479	2,008
Stock-based compensation	2,017	1,859
Capitalized R&D	3,885	1,985
State net operating loss carryover and credits	108	120
Lease Liability	4,841	4,187
Canadian NOL	0	313
U.S. Federal net operating loss carryover and credits	0	52
Deferred income tax asset before valuation allowance	19,917	15,202
Valuation allowance	(108)	(108)
Deferred income tax asset	19,809	15,094
Goodwill, acquisition costs and intangible assets	(7,578)	(3,977)
Depreciation	(3,436)	(2,048)
Right of Use Asset	(4,702)	(4,149)
Deferred income tax liability	(15,716)	(10,174)
Net deferred income tax asset	$ 4,093	$ 4,920

Represents the amount of deferred tax assets attributable to capitalized research and development.

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to lease liability.

+ References

No definition available.

+ Details

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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 state and local operating loss carryforwards and tax credits.

+ References

No definition available.

+ Details

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Namespace Prefix:	lyts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of deferred tax assets, operating loss carryforwards, domestic and tax credit carryforwards.

+ References

No definition available.

+ 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 uncertain tax positions.

+ References

No definition available.

+ Details

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Namespace Prefix:	lyts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

+ Details

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Data Type:	xbrli:monetaryItemType
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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
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

+ 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 employee compensation.

+ References

+ Details

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

- Definition

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

+ 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 accrued liabilities.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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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

+ Details

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Data Type:	xbrli:monetaryItemType
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

+ Details

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

+ References

+ Details

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- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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