Retirement Plans (Assumptions Used) (Details)	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Weighted average used to determine benefit obligations:
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	2.84%	3.26%	4.37%
Weighted average used to determine net periodic cost:
Discount rate	3.26%	4.37%	3.88%
Expected return on plan assets	5.00%	4.93%	4.68%
Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon	10

Defined Benefit Plan, Expected Return on Plan Assets, Major Asset Classes, Time Horizon

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit 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 (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920

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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.

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