Pension Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer		$ 1,978	$ 46,700	$ 12,900
Pension settlement loss		0	66,332	0
Actuarial loss expected to be recognized in the following year		3,400
Actual return on plan assets gain (loss)		1,700	1,900	15,900
U.S. Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer		0	25,475
Pension settlement loss		0	66,332	0
Net periodic pension cost		0	72,136	523
International Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer		1,978	21,225
Pension settlement loss		$ 0	0	0
Long-term rate of return		5.44%
Net periodic pension cost		$ 1,955	$ 1,741	$ 2,771
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, vesting period		1 year
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, vesting period		5 years
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic pension cost	$ 2,700
Germany [Member] | International Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Current asset allocation target for equity securities		60.00%
Current asset allocation target for fixed income securities		40.00%
Other International [Member] | International Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Current asset allocation target for fixed income securities		100.00%