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Note 10 - Employee Benefit Plans (Details Textual) - USD ($) | 12 Months Ended | 36 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Oct. 01, 2016 | Oct. 03, 2015 | Sep. 30, 2017 | Sep. 27, 2014
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement |  | $ (2,539,000) |  |  |
Pension Plan [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  | 0 | 2,201,000 |  | $ 2,253,000
Defined Benefit Plan, Plan Assets, Contributions by Employer |  | 1,919,000 | 234,000 |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement |  | (2,539,000) |  |  |
Pension Plan [Member] | Equity Funds [Member] |  |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  |  | 60.00% |  |
Pension Plan [Member] | Fixed Income Funds [Member] |  |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  |  | 40.00% |  |
Supplemental Employee Retirement Plan [Member] |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer | $ 290,000 | 290,000 | 290,000 |  |
Supplemental Retirement Benefit Period | 15 years |  |  |  |
Defined Benefit Plan Percent of Highest Average Salary Base | 50.00% |  |  |  |
Defined Benefit Plan Number of Years in Average Annual Base Salary | 5 years |  |  |  |
Defined Benefit Plan Number of Years Preceding Retirement for Average Annual Base Salary Calculation | 10 years |  |  |  |
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | $ (150,000) |  |  | $ (150,000) |
Payment for Other Postretirement Benefits | 40,000 | 25,000 | 25,000 |  |
Postemployment Benefits, Period Expense | $ 34,000 | 26,000 | 23,000 |  |
Supplemental Employee Retirement Plan [Member] | Minimum [Member] |  |  |  |  |
Defined Benefit Plan Employment Term | 30 years |  |  |  |
Reduced SERP [Member] |  |  |  |  |
Defined Benefit Plan Retirement Age | 65 |  |  |  |
Defined Benefit Plan, Reduction for Each Month | 0.0028% |  |  | 0.0028% |
Reduced SERP [Member] | Minimum [Member] |  |  |  |  |
Defined Benefit Plan Employment Term | 10 years |  |  |  |
Retirement Savings Plan [Member] |  |  |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent | 75.00% |  |  |  |
Defined Contribution Plan, Cost | $ 1,100,000 | 1,000,000 | 1,000,000 |  |
Retirement Savings Plan, First 1% of Employee Contribution [Member] |  |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  |  |  | 100.00% |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  |  |  | 1.00% |
Retirement Savings Plan, Next 5% of Employee Contribution [Member] |  |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  |  |  | 50.00% |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  |  |  | 5.00% |
VEBA [Member] |  |  |  |  |
Defined Contribution Plan, Cost | 5,600,000 | $ 5,400,000 | $ 6,300,000 |  |
Healthcare Coverage Claims in Excess of | $ 175,000 |  |  |  |

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- Definition The amount of time that a Participant must remain in continuous service with the Company to be eligible for full supplemental retirement benefits. + References No definition available. + Details
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- Definition The number of consecutive years used to determine a Participant's highest average annual base salary in a supplemental employee retirement plan. + References No definition available. + Details
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- Definition Defined benefit plan number of years preceding retirement for average annual base salary calculation + References No definition available. + Details
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- Definition The percentage of a Participant's highest average base salary that will be paid out to the Participant as supplemental retirement benefits if they meet the continuous service requirement. + References No definition available. + Details
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- Definition The benefit will be reduced by a certain percentage for each month short of 30 years that the Participant was employed by the Company assuming the minimum continuous service and age requirements. + References No definition available. + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(ii) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(iv)(01) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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