Note 4 - Stock-Based Compensation (Details) - Stock Option Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Mar. 29, 2014	Sep. 29, 2012
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013 (in Shares)		918
Outstanding at March 29, 2014 (in Shares)	895	918
Outstanding at March 29, 2014	6 years 7 days
Outstanding at March 29, 2014 (in Dollars)	$ 5,318
Vested and anticipated to vest in the future at March 29, 2014 (in Shares)	893
Vested and anticipated to vest in the future at March 29, 2014	6 years 3 days
Vested and anticipated to vest in the future at March 29, 2014 (in Dollars)	5,310
Exercisable at March 29, 2014 (in Shares)	604
Exercisable at March 29, 2014	4 years 233 days
Exercisable at March 29, 2014 (in Dollars)	4,095
Granted (in Shares)	67
Exercised (in Shares)	(90)
Exercised (in Dollars)	$ 804
Minimum [Member]
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013		$ 5.43
Outstanding at March 29, 2014	$ 5.43	$ 5.43
Granted	$ 19.08
Granted	$ 19.08
Granted	$ 19.08
Exercised	$ 6.89
Exercised	$ 6.89
Maximum [Member]
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013		$ 20.27
Outstanding at March 29, 2014	$ 20.27	$ 20.27
Granted	$ 19.08
Granted	$ 19.08
Granted	$ 19.08
Exercised	$ 13.06
Exercised	$ 13.06
Weighted Average [Member]
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013		$ 12.65
Outstanding at March 29, 2014	$ 13.34	$ 12.65
Vested and anticipated to vest in the future at March 29, 2014	$ 13.33
Exercisable at March 29, 2014	$ 12.53
Granted	$ 19.08
Granted	$ 19.08
Granted	$ 19.08
Exercised	$ 10.58
Exercised	$ 10.58

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