Fair Value Measurements (Details1) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Reconciliation of Beginning and Ending Balance for Assets and Liabilities Measured at Fair Value
Beginning balances-Liabilities	$ (16,576)	$ (15,970)
Beginning balance - Assets		8,955
Total gain (loss) included in accumulated other comprehensive loss, liabilities	20	4,690
Total gain (loss) included in accumulated other comprehensive loss, Assets		(6,012)
Total gain included in earnings, Liabilities	567	328
Total gain included in earnings, Assets
Ending balances-Liabilities	(15,989)	(10,952)
Ending balance - Assets		$ 2,943

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Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Amount of gain (loss) recognized in other comprehensive income, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount of gain (loss) recognized in other comprehensive income, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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-Paragraph 32

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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