Credit Facilities, Short-term Borrowings (Narrative) (Details) BRL in Thousands, $ in Thousands	9 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2016 BRL	Jun. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)
Long-term debt, excluding current portion			$ 685,000	$ 850,000
Other Foreign Short-term Borrowings [Member]
Outstanding borrowings			0
Revolving Credit Agreement [Member]
Maximum borrowing capacity			1,000,000
Option to increase maximum borrowings to this amount			$ 1,200,000
Line of Credit Facility, Expiration Date	Apr. 01, 2020
Variable Rate Basis	LIBOR
Credit facility effective interest rate on outstanding borrowing		1.51%	1.51%	1.44%
Deferred financing costs					$ 2,359
Outstanding borrowings			$ 392,000	$ 350,000
Current portion of outstanding borrowings	$ 100,000
Deferred Finance Costs, Gross					$ 2,359
Revolving Credit Agreement [Member] | Minimum [Member]
Basis Spread On Variable Rate	0.85%
Revolving Credit Agreement [Member] | Maximum [Member]
Basis Spread On Variable Rate	1.65%
Chinese Credit Facility [Member]
Maximum borrowing capacity			22,700			$ 22,700
Line of Credit Facility, Expiration Date	Sep. 01, 2016
Outstanding borrowings			0
Chinese Credit Facility, RMB Denominated Loan [Member]
Variable Rate Basis	interest at the prevailing interest rate offered by the People's Bank of China on the date of borrowing, plus a margin equal to 15% of that prevailing rate
Chinese Credit Facility, USD Denominated Loan [Member]
Variable Rate Basis	interest at the lender's cost of borrowing rate at the date of borrowing, plus 3%
Brazil Credit Facility [Member]
Line of Credit Facility, Expiration Date	Jul. 26, 2016
Brazil Credit Facility BRL Denominated Loan [Member]
Maximum borrowing capacity | BRL		BRL 52,000
Variable Rate Basis	interest at the lender's cost of borrowing rate at the date of borrowing, plus 1.75%
Outstanding borrowings			$ 0	$ 2,430