Employee Benefit Plans (Schedule of Target and Actual Asset Allocation) (Details)	Sep. 30, 2020	Sep. 30, 2019
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Target	30.00%	40.00%
Pension Plan \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target	30.00%
Actual	30.00%	40.00%
Pension Plan \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target	70.00%
Actual	69.00%	59.00%
Pension Plan \| Cash
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Actual	1.00%	1.00%
Pension Plan \| Other
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Actual	0.00%	0.00%
Postretirement Plan \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target	50.00%
Actual	51.00%	49.00%
Postretirement Plan \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target	50.00%
Actual	48.00%	50.00%
Postretirement Plan \| Cash
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Actual	1.00%	1.00%
Postretirement Plan \| Other
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Actual	0.00%	0.00%

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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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