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Retirement Plans (Determining The Present Values Of Benefit Obligations And Net Periodic Benefit Costs) (Details) | 12 Months Ended
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Oct. 02, 2016 | Sep. 27, 2015 | Sep. 28, 2014
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Cash flow period extension |  | P30Y |  |
Qualified Pension Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Assumptions used to determine benefit obligations, Discount rate | [1] | 3.85% | 4.79% | 4.60%
Assumptions used to determine benefit obligations, Rate of future pay increases | [1] | 0.00% | 3.50% | 3.50%
Assumptions used to determine net periodic benefit cost, Discount rate | [2] | 4.79% | 4.60% | 5.37%
Assumptions used to determine net periodic benefit cost, Long-term rate of return on assets | [2] | 6.50% | 6.50% | 7.25%
Assumptions used to determine net periodic benefit cost, Rate of future pay increases | [2] | 3.50% | 3.50% | 3.50%
Supplemental Employee Retirement Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Assumptions used to determine benefit obligations, Discount rate | [1] | 3.60% | 4.45% | 4.36%
Assumptions used to determine benefit obligations, Rate of future pay increases | [1] | 3.50% | 3.50% | 3.50%
Assumptions used to determine net periodic benefit cost, Discount rate | [2] | 4.45% | 4.36% | 4.88%
Assumptions used to determine net periodic benefit cost, Rate of future pay increases | [2] | 3.50% | 3.50% | 3.50%
Postretirement Health Plans [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Assumptions used to determine benefit obligations, Discount rate | [1] | 3.64% | 4.47% | 4.43%
Assumptions used to determine net periodic benefit cost, Discount rate | [2] | 4.47% | 4.43% | 5.04%
[1] | Determined as of end of year
[2] | Determined as of beginning of year

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- Definition The interest rate used to adjust for the time value of money for the 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 (k)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + 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 (k)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The interest rate used to adjust for the time value of money. + 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 (k)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition If the assumed rate is benchmarked off published long-term bond indices, disclosure of how the timing and amount of cash outflows related to the bonds included in the indices match the plan's defined benefit payments. If there are differences between the terms of the bonds and the terms of the benefit obligations, disclosure of how the entity adjusts for the difference. + References No definition available. + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512046 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + 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 (k)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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