Derivative Financial Instruments Additional Details (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Sep. 30, 2012
Derivative [Line Items]
Derivative Credit Risk Valuation Adjustment, Derivative Assets	$ 36	$ 46
Letters of Credit Outstanding, Amount	38,491
Other Current Assets [Member]
Derivative [Line Items]
Collateral Already Posted, Aggregate Fair Value	450	50
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	3,697
Derivative, Notional Amount	228,419
Cash Flow Hedging [Member] | Commodity Contract [Member]
Derivative [Line Items]
Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months	(1,010)
Fair Value Hedging [Member]
Derivative [Line Items]
Derivative, Notional Amount	112,737	172,581
Silver, Ounces | Cash Flow Hedging [Member] | Commodity Contract [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,000
Derivative, Notional Amount	5,609
Silver, Ounces | Cash Flow Hedging [Member] | Commodity Contract [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	60,000
Derivative, Notional Amount	$ 1,189