Note 11 - Summary of Securities (Details) - USD ($)	Mar. 26, 2016	Sep. 26, 2015
Corporate Bond Securities [Member]
Held to Maturity - Amortized Cost	$ 95,689,000	$ 66,660,000
Held to Maturity - Gross Unrealized Gains	117,000	15,000
Held to Maturity - Gross Unrealized Losses	969,000	663,000
Held to Maturity - Fair Market Value	94,837,000	66,012,000
Mutual Funds [Member]
Available for Sale - Amortized Cost	$ 15,091,000	$ 20,041,000
Available for Sale - Gross Unrealized Gains
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ 1,240,000	$ 827,000
Available for Sale - Fair Market Value	13,851,000	19,214,000
Certificates of Deposit [Member]
Held to Maturity - Amortized Cost	960,000
Held to Maturity - Gross Unrealized Gains	$ 8,000
Held to Maturity - Gross Unrealized Losses
Held to Maturity - Fair Market Value	$ 968,000
Preferred Stock [Member]
Available for Sale - Amortized Cost	20,473,000	20,473,000
Available for Sale - Gross Unrealized Gains	10,000	114,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	748,000	163,000
Available for Sale - Fair Market Value	19,735,000	20,424,000
Held to Maturity - Amortized Cost	96,649,000	66,660,000
Held to Maturity - Gross Unrealized Gains	125,000	15,000
Held to Maturity - Gross Unrealized Losses	969,000	663,000
Held to Maturity - Fair Market Value	95,805,000	66,012,000
Available for Sale - Amortized Cost	35,564,000	40,514,000
Available for Sale - Gross Unrealized Gains	10,000	114,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	1,988,000	990,000
Available for Sale - Fair Market Value	$ 33,586,000	$ 39,638,000

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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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-Publisher FASB
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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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