Retirement Benefits (Schedule of Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Defined Benefit Pension Plan [Member]
Changes in projected benefit obligation:
Projected benefit obligation at beginning of year	$ 227,499	$ 232,949
Pension obligation assumed in L'Orange aquisition	39,257
Service cost	2,767	2,808	$ 2,444
Interest cost	7,530	6,965	6,873
Net actuarial (gains) losses	(13,511)	(11,455)
Contribution by participants	43	69
Benefits paid	(8,539)	(7,911)
Plan amendments		3,694
Foreign currency exchange rate changes	(1,529)	380
Projected benefit obligation at end of year	253,517	227,499	232,949
Changes in fair value of plan assets:
Fair value of plan assets at beginning of year	224,712	208,812
Actual return (loss) on plan assets	12,034	22,609
Contributions by the Company	994	671
Contributions by plan participants	43	69
Benefits paid (plan assets)	(8,539)	(7,911)
Foreign currency exchange rate changes	(1,522)	462
Fair value of plan assets at end of year	227,722	224,712	208,812
Net over/(under)funded status at end of year	(25,795)	(2,787)
Defined Benefit Pension Plan [Member] \| UNITED STATES
Changes in projected benefit obligation:
Projected benefit obligation at beginning of year	161,130	160,892
Service cost	1,643	1,675	1,695
Interest cost	6,004	5,757	5,236
Net actuarial (gains) losses	(13,128)	(5,267)
Contribution by participants	34	55
Benefits paid	(5,651)	(5,676)
Plan amendments		3,694
Projected benefit obligation at end of year	150,032	161,130	160,892
Changes in fair value of plan assets:
Fair value of plan assets at beginning of year	160,332	145,886
Actual return (loss) on plan assets	10,627	20,067
Contributions by plan participants	34	55
Benefits paid (plan assets)	(5,651)	(5,676)
Fair value of plan assets at end of year	165,342	160,332	145,886
Net over/(under)funded status at end of year	15,310	(798)
Defined Benefit Pension Plan [Member] \| Foreign Plan [Member]
Changes in projected benefit obligation:
Projected benefit obligation at beginning of year	66,369	72,057
Pension obligation assumed in L'Orange aquisition	39,257
Service cost	1,124	1,133	749
Interest cost	1,526	1,208	1,637
Net actuarial (gains) losses	(383)	(6,188)
Contribution by participants	9	14
Benefits paid	(2,888)	(2,235)
Foreign currency exchange rate changes	(1,529)	380
Projected benefit obligation at end of year	103,485	66,369	72,057
Changes in fair value of plan assets:
Fair value of plan assets at beginning of year	64,380	62,926
Actual return (loss) on plan assets	1,407	2,542
Contributions by the Company	994	671
Contributions by plan participants	9	14
Benefits paid (plan assets)	(2,888)	(2,235)
Foreign currency exchange rate changes	(1,522)	462
Fair value of plan assets at end of year	62,380	64,380	62,926
Net over/(under)funded status at end of year	(41,105)	(1,989)
Defined Benefit Pension Plan [Member] \| JAPAN
Changes in projected benefit obligation:
Projected benefit obligation at end of year	10,844
Changes in fair value of plan assets:
Fair value of plan assets at end of year	11,520
Defined Benefit Pension Plan [Member] \| UNITED KINGDOM
Changes in projected benefit obligation:
Projected benefit obligation at end of year	52,260
Changes in fair value of plan assets:
Fair value of plan assets at end of year	50,860
Defined Benefit Pension Plan [Member] \| GERMANY
Changes in projected benefit obligation:
Projected benefit obligation at end of year	40,381
Changes in fair value of plan assets:
Fair value of plan assets at end of year	0
Other Postretirement Benefit Plans [Member]
Changes in projected benefit obligation:
Projected benefit obligation at beginning of year	32,252	35,630
Service cost	7	14	22
Interest cost	1,165	1,244	1,048
Net actuarial (gains) losses	2,716	2,049
Contribution by participants	1,311	1,365
Benefits paid	(3,707)	(3,964)
Curtailment (gain) loss	(330)
Foreign currency exchange rate changes	3	12
Projected benefit obligation at end of year	27,985	32,252	$ 35,630
Changes in fair value of plan assets:
Contributions by the Company	2,396	2,599
Contributions by plan participants	1,311	1,365
Benefits paid (plan assets)	(3,707)	(3,964)
Net over/(under)funded status at end of year	$ (27,985)	$ (32,252)

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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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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

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