Retirement Plans (Schedule Of Plan Asset Allocation) (Details)	12 Months Ended
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

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.

No definition available.

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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

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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

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- Definition

Percentage of actual 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/2009/role/commonPracticeRef
-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

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