Share-Based Compensation (Schedule of Compensation Expenses for Nonvested Share-Based Awards Expected to be Recognized) (Details) In Thousands	6 Months Ended
Jun. 30, 2011
Share-Based Compensation
Remaining six months of 2011	3,099
2012	4,586
2013	2,362
2014	132
Total compensation expenses	10,179

Compensation expense for nonvested share-based awards expected to be recognized in year four.

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Compensation expense for nonvested share-based awards expected to be recognized in year one.

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Compensation expense for nonvested share-based awards expected to be recognized in year three.

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Compensation expense for nonvested share-based awards is expected to be recognized in year two.

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Compensation expense for nonvested share-based awards expected to be recognized, total.

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