Derivatives (Schedule of Derivative Assets Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	$ 2,727	$ 1,924
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair Value of derivative assets, current	1,070	724
Fair Value of derivative assets, noncurrent	112	0
Fair Value of derivative liabilities, current	(3)	(105)
Non Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Fair Value of derivative assets, current	2,218	2,510
Fair Value of derivative liabilities, current	(670)	(1,205)
Derivative Assets (Liabilities), at Fair Value, Net	$ 1,548

Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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Reference 9: http://www.xbrl.org/2003/role/presentationRef

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-Glossary Current Assets

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+ Details

- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References+ Details

- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments which are expected to exist longer than one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

+ Details

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

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-Glossary Current Liabilities

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details