Derivative Financial Instruments and Risk Management (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Fair Value Hedge Assets	$ 4,207	$ 0
Fair Value Hedge Liabilities	0	869
Other Current Assets [Member] | Foreign Exchange Forward [Member]
Fair Value Hedge Assets	875	0
Other Current Assets [Member] | Aluminum Futures [Member]
Fair Value Hedge Assets	3,332	0
Accrued Expenses and Derivative Liabilities [Member] | Foreign Exchange Forward [Member]
Fair Value Hedge Liabilities	0	27
Accrued Expenses and Derivative Liabilities [Member] | Aluminum Futures [Member]
Fair Value Hedge Liabilities	$ 0	$ 842