Note 11 - Summary of Securities (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Sep. 29, 2018
Held-to-maturity securities, amortized cost	$ 136,873	$ 139,813
Held-to-maturity securities, gross unrealized gains	1,016	28
Held-to-maturity securities, gross unrealized losses	125	1,527
Held-to-maturity securities, fair market value	137,764	138,314
Available-for-sale securities, amortized cost	21,230	24,658
Available-for-sale securities, gross unrealized gains	254	380
Available-for-sale securities, gross unrealized losses	452	295
Available-for-sale securities, fair market value	21,032	24,743
Corporate Bond Securities [Member]
Held-to-maturity securities, amortized cost	133,993	136,933
Held-to-maturity securities, gross unrealized gains	1,011	28
Held-to-maturity securities, gross unrealized losses	125	1,520
Held-to-maturity securities, fair market value	134,879	135,441
Mutual Funds [Member]
Available-for-sale securities, amortized cost	5,549	8,978
Available-for-sale securities, gross unrealized gains	0	0
Available-for-sale securities, gross unrealized losses	394	295
Available-for-sale securities, fair market value	5,155	8,683
Certificates of Deposit [Member]
Held-to-maturity securities, amortized cost	2,880	2,880
Held-to-maturity securities, gross unrealized gains	5	0
Held-to-maturity securities, gross unrealized losses	0	7
Held-to-maturity securities, fair market value	2,885	2,873
Preferred Stock [Member]
Available-for-sale securities, amortized cost	15,681	15,680
Available-for-sale securities, gross unrealized gains	254	380
Available-for-sale securities, gross unrealized losses	58	0
Available-for-sale securities, fair market value	$ 15,877	$ 16,060

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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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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