Note 7 - Stock-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
Apr. 03, 2021
Options outstanding, balance (in shares)	482
Weighted average exercise price per share (in dollars per share)	$ 24.90
Options outstanding, granted (in shares)	42
Weighted average exercise price per share, granted (in dollars per share)	$ 29.43
Options outstanding, exercised (in shares)	(24)
Weighted average exercise price per share, exercised (in dollars per share)	$ 17.53
Aggregate intrinsic value, exercised	$ 158
Options outstanding, balance (in shares)	500
Weighted average exercise price per share (in dollars per share)	$ 25.65
Contractual term - weighted average, balance (Year)	6 years 7 months 9 days
Aggregate intrinsic value, balance	$ 3,607
Options outstanding, vested and anticipated to vest in future (in shares)	486
Weighted average exercise price per share, vested and anticipated to vest in futur (in dollars per share)	$ 25.68
Contractual term - weighted average, vested and anticipated to vest in future (Year)	6 years 6 months 10 days
Aggregate intrinsic value, vested and anticipated to vest in future	$ 3,502
Options outstanding, exercisable (in shares)	304
Weighted average exercise price per share, exercisable (in dollars per share)	$ 27.28
Contractual term - weighted average, exercisable (Year)	5 years 25 days
Aggregate intrinsic value, exercisable	$ 1,832
Minimum [Member]
Exercise price per share, balance, lower (in dollars per share)	$ 10.23
Exercise price per share, granted, lower (in dollars per share)	29.43
Exercise price per share, exercised, lower (in dollars per share)	13.06
Exercise price per share, balance, lower (in dollars per share)	10.23
Maximum [Member]
Exercise price per share, balance, upper (in dollars per share)	41.85
Exercise price per share, granted, upper (in dollars per share)	29.43
Exercise price per share, exercised, upper (in dollars per share)	21.57
Exercise price per share, balance, upper (in dollars per share)	$ 41.85

The floor of a customized range of exercise prices for options exercised during the period.

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The ceiling of a customized range of exercise prices for options exercised during the period.

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

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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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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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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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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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

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