Pension Plan and Retirement Benefits - Expected benefit payments (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Defined Benefit Pension Plans
Expected benefit payments
2020	$ 14,858
2021	15,282
2022	15,830
2023	16,281
2024	16,682
2025-2029 (in total)	86,758
Postretirement Health Care Benefits
Expected benefit payments
2020	4,155
2021	4,487
2022	4,794
2023	4,965
2024	4,894
2025-2029 (in total)	$ 23,939

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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

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

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

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

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