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Note 8 - Stock-based Compensation (Tables) | 12 Months Ended
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Sep. 30, 2017
Notes Tables |
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] |
|  | Year Ended |
|  | September 30, |  |  | October 1, |  |  | October 3, |
(In thousands) |  | 2017 |  |  | 2016 |  |  | 2015 |
Stock options: |  |  |  |  |  |  |  |  |  |  |  |
Compensation expense |  | $ | 1,007 |  |  | $ | 988 |  |  | $ | 1,007 |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] |
|  | Year Ended |
|  | Septem ber 30 , |  |  | Octo ber 1 , |  |  | Octo ber 3 , |
|  | 201 7 |  |  | 201 6 |  |  | 201 5 |
Expected term (in years) |  |  | 5.14 |  |  |  | 5.45 |  |  |  | 5.72 |
Risk-free interest rate |  |  | 1.98 | % |  |  | 1.30 | % |  |  | 2.18 | %
Expected volatility |  |  | 38.32 | % |  |  | 39.00 | % |  |  | 37.99 | %
Expected dividend yield |  |  | 0.37 | % |  |  | 0.48 | % |  |  | 0.61 | %
Share-based Compensation, Stock Options, Activity [Table Text Block] |
|  |  |  |  |  | Exercise Price |  |  | Contractual |  |  | Aggregate |
|  |  |  |  |  | Per Share |  |  | Term - |  |  | Intrinsic |
|  | Options |  |  |  |  |  |  |  |  | Weighted |  |  | Weighted |  |  | Value |
(Share amounts in thousands) |  | Outstanding |  |  | Range |  | Average |  |  | Average (in years) |  |  | (in thousands) |
Outstanding at September 27, 2014 |  |  | 871 |  |  |  | $6.89 | - | $20.50 |  |  | $ | 14.23 |  |  |  |  |  |  |  |  |
Granted |  |  | 134 |  |  |  | 18.05 | - | 21.96 |  |  |  | 19.89 |  |  |  |  |  |  |  |  |
Exercised |  |  | (27 | ) |  |  | 6.89 | - | 11.15 |  |  |  | 9.17 |  |  |  |  |  |  | $ | 328 |
Forfeited |  |  | (55 | ) |  |  | 9.16 | - | 21.96 |  |  |  | 15.37 |  |  |  |  |  |  |  |  |
Outstanding at October 3, 2015 |  |  | 923 |  |  |  | 7.55 | - | 21.96 |  |  |  | 15.14 |  |  |  |  |  |  |  |  |
Granted |  |  | 99 |  |  |  | 23.95 | - | 34.49 |  |  |  | 28.47 |  |  |  |  |  |  |  |  |
Exercised |  |  | (651 | ) |  |  | 7.55 | - | 21.96 |  |  |  | 13.93 |  |  |  |  |  |  |  | 8,718 |
Outstanding at October 1, 2016 |  |  | 371 |  |  |  | 9.16 | - | 34.49 |  |  |  | 20.81 |  |  |  |  |  |  |  |  |
Granted |  |  | 88 |  |  |  | 26.75 | - | 37.06 |  |  |  | 30.93 |  |  |  |  |  |  |  |  |
Exercised |  |  | (67 | ) |  |  | 9.16 | - | 23.95 |  |  |  | 19.05 |  |  |  |  |  |  |  | 1,212 |
Outstanding at September 30, 2017 |  |  | 392 |  |  |  | 9.16 | - | 37.06 |  |  |  | 23.40 |  |  |  | 7.64 |  |  |  | 1,845 |
Vested and anticipated to vest in future at September 30, 2017 |  |  | 388 |  |  |  |  |  |  |  |  |  | 23.36 |  |  |  | 7.63 |  |  |  | 1,837 |
Exercisable at September 30, 2017 |  |  | 194 |  |  |  |  |  |  |  |  |  | 19.05 |  |  |  | 6.41 |  |  |  | 1,491 |
Schedule of RSU Grants and Compensation Expense [Table Text Block] |
|  | Year Ended |
|  | September 30, |  |  | October 1, |  |  | October 3, |
(In thousands) |  | 2017 |  |  | 2016 |  |  | 2015 |
Restricted stock unit grants: |  |  |  |  |  |  |  |  |  |  |  |
Units |  |  | 37 |  |  |  | 57 |  |  |  | 62 |
Market value |  | $ | 1,180 |  |  | $ | 1,516 |  |  | $ | 1,253 |
Compensation expense |  |  | 1,238 |  |  |  | 1,451 |  |  |  | 1,291 |
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] |
|  |  |  |  |  | Weighted |
|  | Restricted |  |  | Average |
|  | Stock Units |  |  | Grant Date |
(Unit amounts in thousands) |  | Outstanding |  |  | Fair Value |
Balance, September 27, 2014 |  |  | 197 |  |  | $ | 15.68 |
Granted |  |  | 62 |  |  |  | 20.33 |
Forfeited |  |  | (13 | ) |  |  | 17.52 |
Released |  |  | (89 | ) |  |  | 12.86 |
Balance, October 3, 2015 |  |  | 157 |  |  |  | 18.96 |
Granted |  |  | 57 |  |  |  | 26.57 |
Forfeited |  |  | (2 | ) |  |  | 23.95 |
Released |  |  | (67 | ) |  |  | 17.95 |
Balance, October 1, 2016 |  |  | 145 |  |  |  | 22.35 |
Granted |  |  | 37 |  |  |  | 31.95 |
Released |  |  | (54 | ) |  |  | 20.43 |
Balance, September 30, 2017 |  |  | 128 |  |  |  | 25.92 |

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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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