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Note 10 - Employee Benefit Plans (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Sep. 29, 2018 | Sep. 30, 2017 | Oct. 01, 2016
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement |  |  | $ (2,539,000)
Pension Plan [Member] |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  | 1,919,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement |  |  | $ (2,539,000)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate | 4.00% | 3.75% | 3.75%
Supplemental Employee Retirement Plan [Member] |  |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer | $ 262,000 | $ 290,000 | $ 290,000
Defined Benefit Plan Employment Term | 30 years |  |
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 | $ 140,000 |  |
Reduced SERP [Member] |  |  |
Defined Benefit Plan Retirement Age | 65 |  |
Defined Benefit Plan, Reduction for Each Month | 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 | 1,100,000 | 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 | $ 5,100,000 | $ 5,600,000 | $ 5,400,000
Healthcare Coverage Claims in Excess of | $ 175,000 |  |

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- Definition The minimum amount of years of continuous service required to receive a reduced benefit under the SERP. + 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 The minimum age that an employee may retire at to receive benefits. + References No definition available. + Details
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- Definition Represents the amount at which stop-loss insurance covers the remainder of the claim. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + 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/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=108410482&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=108410482&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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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