Note 11 (Details) - Summary of Securities (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Mar. 28, 2015	Sep. 27, 2014
Note 11 (Details) - Summary of Securities [Line Items]
Amortized cost - available for sale	$ 130,499	$ 129,473
Gross unrealized gains - available for sale	403	760
Gross unrealized losses - available for sale	3,148	2,116
Fair market value - available for sale	127,754us-gaap_AvailableForSaleSecurities	128,117us-gaap_AvailableForSaleSecurities
Amortized cost - held to maturity		2,000
Gross unrealized gains - held to maturity		0
Gross unrealized losses - held to maturity		13
Fair market value - held to maturity		1,987
US Government Corporations and Agencies Securities [Member]
Note 11 (Details) - Summary of Securities [Line Items]
Amortized cost - available for sale	117,366
Gross unrealized gains - available for sale	298
Gross unrealized losses - available for sale	3,130
Fair market value - available for sale	114,534
Amortized cost - held to maturity		2,000
Gross unrealized gains - held to maturity		0
Gross unrealized losses - held to maturity		13
Fair market value - held to maturity		1,987
Preferred Stock [Member]
Note 11 (Details) - Summary of Securities [Line Items]
Amortized cost - available for sale	13,133
Gross unrealized gains - available for sale	105
Gross unrealized losses - available for sale	18
Fair market value - available for sale	13,220
Mutual Funds [Member]
Note 11 (Details) - Summary of Securities [Line Items]
Amortized cost - available for sale		129,473
Gross unrealized gains - available for sale		760
Gross unrealized losses - available for sale		2,116
Fair market value - available for sale		$ 128,117

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

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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