Employee Benefit Plans - Schedule of Weighted Average Assumptions (Details)	Sep. 30, 2020	Sep. 30, 2019
Pension Benefits
Weighted-average assumptions as of September 30
Discount rate	2.71%	3.17%
Expected return on plan assets	4.89%	5.49%
Postretirement Health and Other
Weighted-average assumptions as of September 30
Discount rate	2.36%	3.10%

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

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)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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