Pension Plans - Accounting For The Pension Plans (Details) - Pension Plan	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine benefit obligations at September 30 measurement date, Discount rate	1.10%	0.90%	1.90%
Weighted average assumptions used to determine benefit obligations at September 30 measurement date, Rate of increase in future compensation	2.80%	2.80%	3.00%
Weighted average assumptions used to determine net periodic pension cost for fiscal years ended September 30, Discount rate	0.90%	1.90%	1.80%
Weighted average assumptions used to determine net periodic pension costs for fiscals years ended September 30, Rate of increase of future compensation	2.80%	3.00%	2.80%
Weighted average assumptions used to determine net periodic pension cost for fiscal years ended September 30, Rate of return on plan assets	5.40%	5.40%	5.40%

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

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

+ Details

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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

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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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.

+ References

No definition available.

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