Retirement and Post-Retirement Employee Benefit Plans - Schedule of Expected Benefit Payments Post Retirement Benefit Plan (Details) - Postretirement Plans $ in Thousands	Sep. 30, 2021 USD ($)
Company Payments
2021	$ 17,701
2022	18,031
2023	18,341
2024	18,981
2025	19,414
2026-2030	100,312
Retiree Payments
2021	2,490
2022	2,465
2023	2,404
2024	2,425
2025	2,395
2026-2030	10,641
Subsidy Payments
2021	0
2022	0
2023	0
2024	0
2025	0
2026-2030	0
Total Postretirement Benefits
2022	20,191
2023	20,496
2024	20,745
2025	21,406
2026	21,809
2027-2031	$ 110,953

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

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

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