Retirement and Postretirement Employee Benefit Plans - Schedule of Expected Benefit Payments Post Retirement Benefit Plan (Details) - Postretirement Plan $ in Thousands	Sep. 30, 2023 USD ($)
Company Payments
2024	$ 17,124
2025	17,179
2026	17,228
2027	17,464
2028	17,576
2029-2033	92,555
Retiree Payments
2024	2,257
2025	2,233
2026	2,189
2027	2,095
2028	1,967
2029-2033	9,068
Subsidy Payments
2024	0
2025	0
2026	0
2027	0
2028	0
2029-2033	0
Total Postretirement Benefits
2024	19,381
2025	19,412
2026	19,417
2027	19,559
2028	19,543
2029-2033	$ 101,623

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The amount of the aggregate postretirement benefits estimated to be paid in the five fiscal years thereafter (the aggregate amount of postretirement benefits estimated to be paid in years 6 through 10 after the date of the latest statement of financial position) by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 5 by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 4 by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 1 by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 3 by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 2 by the Company.

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The amount of the postretirement benefits estimated to be paid in Year 5 by the retirees.

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The amount of the postretirement benefits estimated to be paid in Year 4 by the retirees.

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The amount of the postretirement benefits estimated to be paid in Year 1 by the retirees.

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The amount of the postretirement benefits estimated to be paid in Year 3 by the retirees.

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The amount of the postretirement benefits estimated to be paid in Year 2 by the retirees.

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Postretirement Benefits [Abstract]

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Retiree Payments [Abstract]

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Subsidy Payments [Abstract]

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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
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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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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- Definition

Amount of prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-4

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Amount of prescription drug subsidy receipt expected in second fiscal year following current fiscal year.

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