Note 5 - Share-based Compensation and Post-retirement Benefits (Details Textual) - shares	3 Months Ended	9 Months Ended
Jun. 29, 2024	Jun. 24, 2023	Jun. 29, 2024	Jun. 24, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)			0	0
Five Year Options [Member]
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions Volatility Calculation Term	51 months
Ten Year Options [Member]
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions Volatility Calculation Term	10 years
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	14,441	11,964	25,987	21,864
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	2,968	2,169	14,506	21,260

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

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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