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Retirement Plans (Health Care Cost Trend Rates for Postretirement Health Plans) (Details) | Oct. 02, 2022 | Oct. 03, 2021 | Sep. 27, 2020
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Participants under age 65 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Health care cost trend rate for next year | 6.25% | 6.50% | 6.75%
Rate to which the cost trend rate is assumed to decline | 4.50% | 4.50% | 4.50%
Participants age 65 or older |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Health care cost trend rate for next year | 5.75% | 6.00% | 6.25%
Rate to which the cost trend rate is assumed to decline | 4.50% | 4.50% | 4.50%

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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + 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 (l) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. + 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 (l) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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