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

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=118257860&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=118255775&loc=d3e1928-114920

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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=118255775&loc=d3e1928-114920

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Retirement and Post-Retirement Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details) - Defined Benefit Plan	Sep. 30, 2020	Sep. 30, 2019
Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	45.30%	40.60%
International equities
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	15.60%	14.50%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	17.00%	18.80%
Company stock
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	13.00%	15.40%
Other assets
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	9.10%	10.70%
Minimum \| Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	35.00%
Minimum \| International equities
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	10.00%
Minimum \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	5.00%
Minimum \| Company stock
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	0.00%
Minimum \| Other assets
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	0.00%
Maximum \| Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	55.00%
Maximum \| International equities
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	20.00%
Maximum \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	30.00%
Maximum \| Company stock
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	15.00%
Maximum \| Other assets
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation Range	20.00%