Note 10 - Cash Dividends (Details Textual) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Nov. 26, 2024	Sep. 30, 2024	Sep. 30, 2023
Payments of Dividends		$ 1.5	$ 1.4
Dividends Accrued		$ 0.2	$ 0.1
O 2025 A Dividends [Member]
Dividends Payable, Amount Per Share		$ 0.2
Subsequent Event [Member] \| O 2025 Q2 Dividends [Member]
Dividends Payable, Amount Per Share	$ 0.05
Dividends Payable, Date to be Paid	Nov. 26, 2024
Dividends Payable, Date of Record	Nov. 18, 2024

Dividends declared but unpaid on equity securities issued by the entity during the period.

No definition available.

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

- Definition

Date the declared dividend will be paid, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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