Derivative Instruments and Hedging Activities (Details 4) (Other Income Expense [Member], Forward Exchange Contract [Member], Not Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Other Income Expense [Member] | Forward Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Undesignated hedges
Amount of Gain (Loss) Recognized in Income on Derivative	$ 8,903	$ 25,644	$ 6,032	$ 8,143