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Retirement Plans (Schedule Of Future Cash Flows) (Details) - USD ($) | 9 Months Ended |  |
--- | --- | --- | ---
Jul. 08, 2018 | Sep. 30, 2018 | Jan. 01, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |
Minimum required contribution for retirement plans |  |  | $ 0
SERP |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net year-to-date contributions | $ 3,299,000 |  |
Postretirement Healthcare Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net year-to-date contributions | $ 1,085,000 |  |
Forecast | SERP |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Remaining estimated net contributions during fiscal 2018 |  | $ 1,100,000 |
Forecast | Postretirement Healthcare Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Remaining estimated net contributions during fiscal 2018 |  | $ 200,000 |

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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 of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year. + References Reference 1: 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 + Details
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