Note 11 - Summary of Securities (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Sep. 30, 2017
Held-to-maturity securities, amortized cost	$ 131,511	$ 120,021
Held-to-maturity securities, gross unrealized gains	173	442
Held-to-maturity securities, gross unrealized losses	551	156
Held-to-maturity securities, fair market value	131,133	120,307
Available-for-sale securities, amortized cost	29,794	29,794
Available-for-sale securities, gross unrealized gains	666	788
Available-for-sale securities, gross unrealized losses	310	322
Available-for-sale securities, fair market value	30,150	30,260
Corporate Bond Securities [Member]
Held-to-maturity securities, amortized cost	125,591	114,101
Held-to-maturity securities, gross unrealized gains	165	424
Held-to-maturity securities, gross unrealized losses	551	155
Held-to-maturity securities, fair market value	125,205	114,370
Mutual Funds [Member]
Available-for-sale securities, amortized cost	13,003	13,003
Available-for-sale securities, gross unrealized gains	58	77
Available-for-sale securities, gross unrealized losses	237	240
Available-for-sale securities, fair market value	12,824	12,840
Certificates of Deposit [Member]
Held-to-maturity securities, amortized cost	5,920	5,920
Held-to-maturity securities, gross unrealized gains	8	18
Held-to-maturity securities, gross unrealized losses		1
Held-to-maturity securities, fair market value	5,928	5,937
Preferred Stock [Member]
Available-for-sale securities, amortized cost	16,791	16,791
Available-for-sale securities, gross unrealized gains	608	711
Available-for-sale securities, gross unrealized losses	73	82
Available-for-sale securities, fair market value	$ 17,326	$ 17,420

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

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