Summary of the Location and Fair Value of Derivative Financial Instruments Reported in the Consolidated Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2011
Cross currency swap [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative instruments in hedges, net investment in foreign operations, liabilities, fair value	$ 21,697	$ 2,008
Costless collar contracts [Member] | Accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Cash flow hedge derivative instrument assets at fair value	3,726	2,466
Costless collar contracts [Member] | Other accrued liabilities [Member]
Derivatives, Fair Value [Line Items]
Cash flow hedge derivative instrument liabilities at fair value	645	552
Forward exchange contract [Member] | Accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Cash flow hedge derivative instrument assets at fair value	$ (2,772)	$ 1,887