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Note 11 (Details Textual) - USD ($) | 3 Months Ended |
--- | --- | ---
Dec. 28, 2019 | Dec. 29, 2018 | Sep. 28, 2019
Debt Securities, Held-to-maturity, Total | $ 118,883,000 |  | $ 130,451,000
Proceeds from Sale and Maturity of Marketable Securities, Total | 18,782,000 | $ 17,125,000 |
Marketable Securities, Gain (Loss), Total | (11,000) | (1,027,000) |
Marketable Securities, Unrealized Gain (Loss), Total | 71,000 | $ (1,027,000) |
Corporate Bond Securities [Member] |  |  |
Debt Securities, Held-to-maturity, Total | $ 106,000,000 |  |
Investment Securities Maturity Term | 2 years |  |

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