Derivative Instruments and Hedging Activities (Details 2) (Instruments designated as accounting hedges:, USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Sep. 30, 2012
Derivative instruments and hedging activities
Asset derivatives:	$ 8,130	$ 7,492
Liability derivatives:	13,979	13,337
Foreign currency forwards | Other current assets
Derivative instruments and hedging activities
Asset derivatives:	2,827	3,779
Foreign currency forwards | Other noncurrent assets
Derivative instruments and hedging activities
Asset derivatives:	5,303	3,713
Foreign currency forwards | Other current liabilities
Derivative instruments and hedging activities
Liability derivatives:	6,809	6,839
Foreign currency forwards | Other noncurrent liabilities
Derivative instruments and hedging activities
Liability derivatives:	7,006	6,407
Forward starting swap | Other noncurrent liabilities
Derivative instruments and hedging activities
Liability derivatives:	$ 164	$ 91