Note 6 - Share-based Compensation and Post-retirement Benefits (Details Textual) - shares	3 Months Ended	6 Months Ended
Mar. 25, 2023	Mar. 26, 2022	Mar. 25, 2023	Mar. 26, 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	0
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period	0	0	9,900	8,873
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period	0	0	18,641	8,868

The term calculated for volatility in fair value assumptions.

No definition available.

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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

Number of shares issued under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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