Long-term Debt (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended									6 Months Ended			3 Months Ended	6 Months Ended			6 Months Ended			6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 The Notes [Member]	Mar. 31, 2014 Non Floating Rate Notes [Member]	Mar. 31, 2014 2008 Note Purchase Agreement [Member]	Mar. 31, 2014 2009 Note Purchase Agreement [Member]	Mar. 31, 2014 2013 Note Purchase Agreement [Member]	Mar. 31, 2014 Floating Rate Notes [Member]	Mar. 31, 2014 Series J Notes [Member]	Mar. 31, 2014 First Closing Notes [Member]	Mar. 31, 2014 Second Closing Notes [Member]	Mar. 31, 2014 Foreign Lines of Credit And Overdraft Facilities [Member]	Dec. 31, 2013 Domestic Line Of Credit [Member]	Mar. 31, 2014 Domestic Line Of Credit [Member]	Mar. 31, 2014 Revolving Credit Facility [Member]	Sep. 30, 2013 Revolving Credit Facility [Member]	Mar. 31, 2014 Revolving Credit Facility [Member] Minimum [Member]	Mar. 31, 2014 Revolving Credit Facility [Member] Maximum [Member]	Mar. 31, 2014 Chinese Credit Facility [Member]	Mar. 31, 2014 Chinese Credit Facility, RMB Denominated Loan [Member]	Mar. 31, 2014	Mar. 31, 2014 Revolving Credit Agreement [Member]	Mar. 31, 2014 Revolving Credit Agreement [Member]
Issuance Date					Oct. 01, 2008	Apr. 01, 2009	Oct. 01, 2013			Oct. 01, 2013	Nov. 15, 2013
Face Amount							$ 250,000
Variable Rate Basis														prime rate or an adjusted LIBOR			0.85%	1.65%		interest at the prevailing interest rate offered by the People's Bank of China on the date of borrowing, plus a margin equal to 25% of that prevailing rate	interest at the lender's cost of borrowing rate at the date of borrowing, plus 3%	LIBOR
Effective Interest Rate on Note									1.49%
Debt Covenant, Leverage Ratio, Maximum			3.5 to 1.0																			3.5 to 1.0
Debt Covenant, Minimum Consolidated Net Worth Calculation, Base Value			800,000																			800,000
Debt Covenant, Minimum Consolidated Net Worth Calculation, Percentage of Net Income			50.00%																			50.00%
Debt Covenant, Minimum Consolidated Net Worth Calculation, Percentage of Net Proceeds of Issuance of Capital Stock																						50.00%
Debt Covenant, Calculations, Period Of Time			rolling four quarter basis
Cross default provisions related to the Company’s other outstanding debt arrangements in excess of this amount, the occurrence of which would permit the lenders to accelerate the amounts due thereunder			60,000
Debt Covenant, Leverage Ratio During Material Acquisition Period, Maximum			4.0 to 1.0																			4.0 to 1.0
Debt Covenant, Maximum Percentage of Priority Debt To Consolidated Net Worth			25.00%
Prepayment, Maximum Percentage of Principal			100.00%
Prepayment, Partial Payment Minimum			1,000
Prepayment, Make-Whole Amount Computation, Discount Rate Basis Points				50
Debt Instrument Prepayment Make Whole Amount Computation				discounting the remaining scheduled payments of interest and principal of the Notes being prepaid at a discount rate equal to the sum of 50 basis points and the yield to maturity of U.S. Treasury securities having a maturity equal to the remaining average life of the Notes being prepaid.				computed as a percentage of the principal amount of such floating rate Notes equal to (a) 2%, on or prior to November 15, 2014, (b) 1%, after November 15, 2014 and on or prior to November 15, 2015, and (c) 0% after November 15, 2015
Debt financing costs	1,297	0					1,400
Line of Credit Facility, Initiation Date													Dec. 21, 2012
Line of Credit Facility, Expiration Date													Dec. 20, 2013									Jul. 01, 2018
Line of Credit Facility, Maximum Borrowing Capacity													200,000						22,700				600,000
Outstanding borrowings												$ 0			$ 105,000	$ 0			$ 0
Credit facility effective interest rate on outstanding borrowing															1.20%