Employee Benefit Plans - Schedule of Expected Benefit Payments (Details) $ in Thousands	Sep. 30, 2017 USD ($)
Pension Benefits [Member]
Projected Contributions and Benefit Payments by Fiscal Year [Abstract]
2018	$ 27,178
2019	10,212
2020	9,383
2021	9,760
2022	8,761
2023 through 2027	36,652
Retiree Health and Life Benefits [Member]
Projected Contributions and Benefit Payments by Fiscal Year [Abstract]
2018	1,243
2019	1,166
2020	1,074
2021	988
2022	901
2023 through 2027	$ 3,231

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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

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- Definition

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.

+ References

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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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