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Note 7 - Stock-based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 6 Months Ended
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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

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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