Note 4 - Stock-Based Compensation (Details) - Stock Option Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Jun. 28, 2014
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013 (in Shares)	918
Outstanding at June 28, 2014 (in Shares)	872
Outstanding at June 28, 2014	5 years 335 days
Outstanding at June 28, 2014 (in Dollars)	$ 5,589
Vested and anticipated to vest in the future at June 28, 2014 (in Shares)	870
Vested and anticipated to vest in the future at June 28, 2014	5 years 332 days
Vested and anticipated to vest in the future at June 28, 2014 (in Dollars)	5,580
Exercisable at June 28, 2014 (in Shares)	581
Exercisable at June 28, 2014	4 years 200 days
Exercisable at June 28, 2014 (in Dollars)	4,180
Granted (in Shares)	67
Exercised (in Shares)	(113)
Exercised (in Dollars)	$ 1,074
Minimum [Member]
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013	$ 5.43
Outstanding at June 28, 2014	$ 5.43
Granted	$ 19.08
Exercised	$ 5.43
Maximum [Member]
Note 4 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 28, 2013	$ 20.27
Outstanding at June 28, 2014	$ 20.27
Granted	$ 19.08
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 June 28, 2014	$ 13.47
Vested and anticipated to vest in the future at June 28, 2014	$ 13.47
Exercisable at June 28, 2014	$ 12.70
Granted	$ 19.08
Exercised	$ 10.10

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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