Postretirement Benefits - Fair Value of Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of assets at beginning of fiscal year	$ 2,225	$ 4,532
Fair value of assets through acquisition	5,052
Actual return on plan assets	69	55
Disbursements	(685)	(51)
Employer contributions	266	153
Employee contributions	191	101
Settlements paid		(2,526)
Foreign currency translation	(40)	(39)
Fair value of assets at end of fiscal year	$ 7,078	$ 2,225

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

Amount of increase in plan assets of defined benefit plan from business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount of contributions received by defined benefit plan from participant which increases plan assets.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

+ Details

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

+ References

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