Note 9 - Cash Dividends (Details Textual) - USD ($)	1 Months Ended	3 Months Ended
Nov. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Payments of Dividends, Total		$ 1,319,000	$ 1,296,000
Dividends Accrued		$ 34,842	$ 31,553
Forecast [Member]
Annual Indicated per Share Dividend Rate	$ 0.20
Subsequent Event [Member]
Quarterly Indicated Per Share Dividend Rate	$ 0.05
Dividends Payable, Date to be Paid	Nov. 26, 2019
Dividends Payable, Date of Record	Nov. 18, 2019

The indicated per share dividend rate for a specific fiscal year.

No definition available.

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Namespace Prefix:	lyts_
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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	lyts_
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Period Type:	duration

- Definition

The indicated per share quarterly cash dividend rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	lyts_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

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