Retirement Benefits (Schedule of Changes in accumulated other comprehensive losses for the defined benefit plans) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Net (gain) loss arising during the period	$ 19,718	$ 26,866	$ (3,746)
Prior service (benefit) cost	0	0	3,355
Loss (gain) due to settlement or curtailment arising during the period	(47)	0	7,539
Amortization of: Net gains (losses)	(1,694)	(513)	(785)
Amortization of: Prior service benefit (cost)	(226)	(225)	66
Foreign currency exchange rate changes	(2,239)	(867)	(104)
Pension Plans, Defined Benefit [Member]
Accumulated other comprehensive loss (earnings), beginning of year	44,720	26,393
Net (gain) loss arising during the period	17,806	20,161
Loss (gain) due to settlement or curtailment arising during the period	(47)	0
Amortization of: Net gains (losses)	(1,538)	(586)
Amortization of: Prior service benefit (cost)	(384)	(383)
Foreign currency exchange rate changes	(2,223)	(865)
Accumulated other comprehensive loss (earning), end of year	58,334	44,720	26,393
United States Pension Plans of US Entity, Defined Benefit [Member]
Accumulated other comprehensive loss (earnings), beginning of year	31,102	14,491
Net (gain) loss arising during the period	8,160	17,390
Loss (gain) due to settlement or curtailment arising during the period	(47)	0
Amortization of: Net gains (losses)	(1,292)	(396)
Amortization of: Prior service benefit (cost)	(384)	(383)
Accumulated other comprehensive loss (earning), end of year	37,539	31,102	14,491
Foreign Pension Plans, Defined Benefit [Member]
Accumulated other comprehensive loss (earnings), beginning of year	13,618	11,902
Net (gain) loss arising during the period	9,646	2,771
Loss (gain) due to settlement or curtailment arising during the period	0	0
Amortization of: Net gains (losses)	(246)	(190)
Amortization of: Prior service benefit (cost)	0	0
Foreign currency exchange rate changes	(2,223)	(865)
Accumulated other comprehensive loss (earning), end of year	20,795	13,618	11,902
Other Postretirement Benefit Plans, Defined Benefit [Member]
Accumulated other comprehensive loss (earnings), beginning of year	3,268	(3,666)
Net (gain) loss arising during the period	1,912	6,705
Amortization of: Net gains (losses)	(156)	73
Amortization of: Prior service benefit (cost)	158	158
Foreign currency exchange rate changes	(16)	(2)
Accumulated other comprehensive loss (earning), end of year	$ 5,166	$ 3,268	$ (3,666)

The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Amount before tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount before tax of gain (loss) adjustment to other comprehensive income (loss) resulting from settlement or curtailment of defined benefit pension and other postretirement defined benefit plans.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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The amount of increase or decrease in amounts recognized in other comprehensive income (but not yet recognized in net periodic benefit cost) for defined benefit plans attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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