Retirement Benefits (Schedule of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Pension Plans, Defined Benefit [Member]
Service cost	$ 605	$ 609	$ 1,216	$ 1,469
Interest cost	1,735	1,720	3,470	3,472
Expected return on plan assets	(3,271)	(3,201)	(6,544)	(6,440)
Amortization of: Net (gains) losses	589	386	1,180	774
Amortization of: Prior service (benefit) cost	96	96	192	192
Net periodic retirement (benefit) cost	(246)	(390)	(486)	(533)
Contributions paid - pensions	101	139	466	528
United States Pension Plans of US Entity, Defined Benefit [Member]
Service cost	418	424	837	1,098
Interest cost	1,439	1,309	2,878	2,626
Expected return on plan assets	(2,633)	(2,535)	(5,265)	(5,077)
Amortization of: Net (gains) losses	463	323	927	646
Amortization of: Prior service (benefit) cost	96	96	192	192
Net periodic retirement (benefit) cost	(217)	(383)	(431)	(515)
Contributions paid - pensions	0	0	0	0
Foreign Pension Plans, Defined Benefit [Member]
Service cost	187	185	379	371
Interest cost	296	411	592	846
Expected return on plan assets	(638)	(666)	(1,279)	(1,363)
Amortization of: Net (gains) losses	126	63	253	128
Amortization of: Prior service (benefit) cost	0	0	0	0
Net periodic retirement (benefit) cost	(29)	(7)	(55)	(18)
Contributions paid - pensions	101	139	466	528
Other Postretirement Benefit Plans, Defined Benefit [Member]
Service cost	3	6	7	11
Interest cost	311	262	622	524
Amortization of: Net (gains) losses	51	39	101	78
Amortization of: Prior service (benefit) cost	(39)	(39)	(79)	(79)
Net periodic retirement (benefit) cost	326	268	651	534
Contributions paid - other postretirement plans	$ 804	$ 840	$ 1,419	$ 1,221

The amount of gains or losses recognized in net periodic benefit cost.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Prior Service Cost
-URI http://asc.fasb.org/extlink&oid=49177896

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512171

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-Publisher FASB
-Name Accounting Standards Codification
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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ 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)
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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ 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)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Service Cost (Component of Net Periodic Pension Cost)
-URI http://asc.fasb.org/extlink&oid=6525008

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-Publisher FASB
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The amount of cash or cash equivalents contributed during the reporting period by the entity to fund non-pension postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 25
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The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

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