Retirement Benefits (Schedule of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 4	$ 5	$ 11
Interest cost	291	311	874	933
Amortization of: Net (gains) losses	24	50	72	151
Amortization of: Prior service (benefit) cost	(40)	(40)	(119)	(119)
Curtailment (gain) loss			(330)
Net periodic retirement (benefit) cost	276	325	502	976
Contributions paid - other postretirement plans	595	592	1,830	2,011
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	693	611	1,838	1,827
Interest cost	1,887	1,744	5,562	5,215
Expected return on plan assets	(3,607)	(3,288)	(10,817)	(9,832)
Amortization of: Net (gains) losses	224	594	670	1,774
Amortization of: Prior service (benefit) cost	177	95	532	287
Net periodic retirement (benefit) cost	(626)	(244)	(2,215)	(729)
Contributions paid - pensions	227	99	658	565
Defined Benefit Pension Plan [Member] \| UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Service cost	410	419	1,232	1,256
Interest cost	1,501	1,439	4,503	4,318
Expected return on plan assets	(2,904)	(2,632)	(8,711)	(7,897)
Amortization of: Net (gains) losses	150	464	449	1,391
Amortization of: Prior service (benefit) cost	177	95	532	287
Net periodic retirement (benefit) cost	(666)	(215)	(1,995)	(645)
Contributions paid - pensions	0	0	0	0
Defined Benefit Pension Plan [Member] \| Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	283	192	606	571
Interest cost	386	305	1,059	897
Expected return on plan assets	(703)	(656)	(2,106)	(1,935)
Amortization of: Net (gains) losses	74	130	221	383
Amortization of: Prior service (benefit) cost	0	0	0	0
Net periodic retirement (benefit) cost	40	(29)	(220)	(84)
Contributions paid - pensions	$ 227	$ 99	$ 658	$ 565

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of cost recognized for passage of time related to defined benefit plan.

+ 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 (h)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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-Publisher FASB
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-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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Amount of payment for other postretirement benefits. Excludes pension benefits.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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Amount of payment for pension benefits. Excludes other postretirement benefits.

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