Note 6 - Share-based Compensation and Post-retirement Benefits (Details Textual) - $ / shares	3 Months Ended	9 Months Ended	12 Months Ended
Jun. 24, 2023	Jun. 25, 2022	Jun. 24, 2023	Jun. 25, 2022	Sep. 24, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term			51 months
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions Volatility Calculation Term			10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)			0	115,700	115,700
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)				$ 23.36	$ 23.36
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period	11,964	327	21,864	9,200
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period	2,619	0	21,260	8,868

The term calculated for volatility in fair value assumptions.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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