Note 5 - Stock-Based Compensation (Details) - Stock Option Activity (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Jun. 29, 2013
Note 5 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 29, 2012 (in Shares)	1,160
Outstanding at June 29, 2013 (in Shares)	860
Outstanding at June 29, 2013 (in Dollars)	$ 4,657
Outstanding at June 29, 2013	6 years 222 days
Vested and anticipated to vest in the future at June 29, 2013 (in Shares)	853
Vested and anticipated to vest in the future at June 29, 2013	6 years 219 days
Vested and anticipated to vest in the future at June 29, 2013 (in Dollars)	4,627
Exercisable at June 29, 2013 (in Shares)	520
Exercisable at June 29, 2013	5 years 102 days
Exercisable at June 29, 2013 (in Dollars)	2,783
Granted (in Shares)	65
Exercised (in Shares)	(365)
Exercised (in Dollars)	$ 2,691
Minimum [Member]
Note 5 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 29, 2012	$ 0.36
Outstanding at June 29, 2013	$ 5.43
Granted	$ 16.45
Exercised	$ 0.36
Maximum [Member]
Note 5 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 29, 2012	$ 20.27
Outstanding at June 29, 2013	$ 20.27
Granted	$ 16.45
Exercised	$ 12.43
Weighted Average [Member]
Note 5 - Stock-Based Compensation (Details) - Stock Option Activity [Line Items]
Outstanding at September 29, 2012	$ 11.09
Outstanding at June 29, 2013	$ 12.27
Vested and anticipated to vest in the future at June 29, 2013	$ 12.27
Exercisable at June 29, 2013	$ 12.45
Granted	$ 16.45
Exercised	$ 9.25

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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