Note 6 - Stock-Based Compensation - Stock Option Activity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Dec. 27, 2014	Sep. 27, 2014
Outstanding (in shares)	871,000
Exercised (in shares)	0
Outstanding (in shares)	871,000
Outstanding	6 years 58 days
Outstanding	$ 7,947
Vested and anticipated to vest in the future (in shares)	869,000
Vested and anticipated to vest in the future	6 years 54 days
Vested and anticipated to vest in the future	7,935
Exercisable (in shares)	594,000
Exercisable	4 years 357 days
Exercisable	$ 6,246
Maximum [Member]
Outstanding (in dollars per share)		$ 20.50
Outstanding (in dollars per share)	$ 20.50	$ 20.50
Minimum [Member]
Outstanding (in dollars per share)		$ 6.89
Outstanding (in dollars per share)	$ 6.89	$ 6.89
Weighted Average [Member]
Outstanding (in dollars per share)		$ 14.23
Outstanding (in dollars per share)	$ 14.23	$ 14.23
Vested and anticipated to vest in the future (in dollars per share)	$ 14.23
Exercisable (in dollars per share)	$ 12.85

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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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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Number of share options (or share units) exercised during the current period.

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