Employee Retirement Plans - Expected Payments for Pension Benefits and Other Postretirement Welfare Benefits (Details) $ in Thousands	Sep. 30, 2017 USD ($)
Pension Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
Fiscal 2018	$ 27,176
Fiscal 2019	28,471
Fiscal 2020	29,812
Fiscal 2021	31,084
Fiscal 2022	32,323
Fiscal 2023 - 2027	179,945
Other Postretirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
Fiscal 2018	566
Fiscal 2019	566
Fiscal 2020	552
Fiscal 2021	537
Fiscal 2022	540
Fiscal 2023 - 2027	$ 2,710

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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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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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