Note C - Investment Securities - Summary of Securities (Details) - USD ($) $ in Thousands	Sep. 29, 2018	Sep. 30, 2017
Held-to-maturity securities, amortized cost	$ 139,813	$ 120,021
Held-to-maturity securities, gross unrealized gains	28	442
Held-to-maturity securities, gross unrealized losses	1,527	156
Held-to-maturity securities, fair market value	138,314	120,307
Available-for-sale securities, amortized cost	24,658	29,794
Available-for-sale securities, gross unrealized gains	380	788
Available-for-sale securities, gross unrealized losses	295	322
Available-for-sale securities, fair market value	24,743	30,260
Corporate Bond Securities [Member]
Held-to-maturity securities, amortized cost	136,933	114,101
Held-to-maturity securities, gross unrealized gains	28	424
Held-to-maturity securities, gross unrealized losses	1,520	155
Held-to-maturity securities, fair market value	135,441	114,370
Mutual Funds [Member]
Available-for-sale securities, amortized cost	8,978	13,003
Available-for-sale securities, gross unrealized gains		77
Available-for-sale securities, gross unrealized losses	295	240
Available-for-sale securities, fair market value	8,683	12,840
Certificates of Deposit [Member]
Held-to-maturity securities, amortized cost	2,880	5,920
Held-to-maturity securities, gross unrealized gains		18
Held-to-maturity securities, gross unrealized losses	7	1
Held-to-maturity securities, fair market value	2,873	5,937
Preferred Stock [Member]
Available-for-sale securities, amortized cost	15,680	16,791
Available-for-sale securities, gross unrealized gains	380	711
Available-for-sale securities, gross unrealized losses		82
Available-for-sale securities, fair market value	$ 16,060	$ 17,420

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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