Note 9 - Stock-Based Compensation (Details) - Stock Option Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Sep. 27, 2014	Sep. 28, 2013	Sep. 29, 2012
Note 9 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding (in Shares)	918	1,160	994
Outstanding at September 27, 2014 (in Shares)	871	918	1,160
Outstanding at September 27, 2014	6 years 149 days
Outstanding at September 27, 2014 (in Dollars)	$ 5,866
Vested and anticipated to vest in future at September 27, 2014 (in Shares)	869
Vested and anticipated to vest in future at September 27, 2014	6 years 146 days
Vested and anticipated to vest in future at September 27, 2014 (in Dollars)	5,858
Exercisable at September 27, 2014 (in Shares)	594
Exercisable at September 27, 2014	5 years 83 days
Exercisable at September 27, 2014 (in Dollars)	4,826
Granted (in Shares)	136	131	178
Excercise (in Shares)	(183)	(373)	(12)
Exercise Intrinsic Value (in Dollars)	$ 1,789	$ 2,744	$ 147
Minimum [Member]
Note 9 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding	$ 5.43	$ 0.36	$ 0.18
Outstanding at September 27, 2014	$ 6.89	$ 5.43	$ 0.36
Granted Weighted Average	$ 19.08	$ 16.45	$ 10.23
Exercise Weighted Average	$ 5.43	$ 0.36	$ 0.18
Maximum [Member]
Note 9 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding	$ 20.27	$ 20.27	$ 20.27
Outstanding at September 27, 2014	$ 20.50	$ 20.27	$ 20.27
Granted Weighted Average	$ 20.50	$ 17.22	$ 13.06
Exercise Weighted Average	$ 20.27	$ 12.43	$ 0.18
Weighted Average [Member]
Note 9 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding	$ 12.65	$ 11.09	$ 10.89
Outstanding at September 27, 2014	$ 14.23	$ 12.65	$ 11.09
Vested and anticipated to vest in future at September 27, 2014	$ 14.23
Exercisable at September 27, 2014	$ 12.85
Granted Weighted Average	$ 19.80	$ 16.84	$ 11.44
Exercise Weighted Average	$ 10.42	$ 9.27	$ 0.18

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