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Note 11 - Employee Benefit Plans (Details Textual) - USD ($) | 12 Months Ended
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Sep. 28, 2019 | Sep. 29, 2018 | Sep. 30, 2017
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | $ 293,000 |  |
Supplemental Employee Retirement Plan [Member] |  |  |
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 |  |
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% |  |
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 | $ 1,200,000 | $ 1,100,000 | $ 1,100,000
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 | $ 5,800,000 | $ 5,100,000 | $ 5,600,000
Healthcare Coverage Claims in Excess of | $ 175,000 |  |

X
- Definition The number of years of continuous service required to receive a benefit under the SERP. + References No definition available. + Details
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X
- 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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X
- 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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X
- 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 The maximum period of time that a Participant will be paid supplemental retirement benefits if they are eligible for full benefits. + References No definition available. + 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=118255775&loc=d3e1928-114920 + Details
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X
- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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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X
- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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