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Retirement Plans (Schedule Of Plan Asset Allocation) (Details) | 12 Months Ended
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Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 100.00%
Asset Allocation, Target, Equity securities | 100.00%
Cash and Cash Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 1.00%
Asset Allocation, Target, Equity securities | 0.00%
Core Fixed Funds Member |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 35.00%
Asset Allocation, Target, Equity securities | 32.00%
High yield |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 3.00%
Asset Allocation, Target, Equity securities | 4.00%
Alternatives |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 8.00%
Asset Allocation, Target, Equity securities | 8.00%
Real Estate [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 8.00%
Asset Allocation, Target, Equity securities | 7.00%
Real Return Bonds Member |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 0.00%
Asset Allocation, Target, Equity securities | 4.00%
UNITED STATES | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 23.00%
Asset Allocation, Target, Equity securities | 23.00%
Non-US [Member] | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Percentage of Plan Assets, Equity securities | 22.00%
Asset Allocation, Target, Equity securities | 22.00%
Minimum [Member] | Cash and Cash Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0
Minimum [Member] | Core Fixed Funds Member |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.27
Minimum [Member] | High yield |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0
Minimum [Member] | Alternatives |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0
Minimum [Member] | Real Estate [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.02
Minimum [Member] | Real Return Bonds Member |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0
Minimum [Member] | UNITED STATES | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.12
Minimum [Member] | Non-US [Member] | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.12
Maximum [Member] | Cash and Cash Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0
Maximum [Member] | Core Fixed Funds Member |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.37
Maximum [Member] | High yield |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.08
Maximum [Member] | Alternatives |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.08
Maximum [Member] | Real Estate [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.12
Maximum [Member] | Real Return Bonds Member |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.08
Maximum [Member] | UNITED STATES | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.32
Maximum [Member] | Non-US [Member] | Equity Funds & Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description | 0.32

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- Definition Description of investment policy and strategy for defined benefit plan asset. Includes, but is not limited to, investment allocation decision and factor pertinent to understanding investment policy and strategy for plan asset. Factor includes, but is not limited to, investment goal, risk management practice, permitted and prohibited investment including use of derivative, diversification, and relationship between plan asset and obligation. + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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