Pension Plan and Retirement Benefits - Expected benefit payments (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Defined Benefit Pension Plan
Expected benefit payments
2023	$ 15,738
2024	16,081
2025	16,366
2026	16,573
2027	16,802
2028-2032 (in total)	83,895
Defined Benefit Other Postretirement Benefit Plan
Expected benefit payments
2023	4,828
2024	4,841
2025	4,890
2026	5,068
2027	5,007
2028-2032 (in total)	$ 25,956

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ 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 (f)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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