Acquisitions (Details 2) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Business Acquisition Pro Forma Financial information
Revenue	$ 19,318		$ 23,341
Net Income	1,108		1,616
Supplemental proforma revenue	389,648	383,333	1,173,830	1,117,245
Supplemental pro forma net income (loss)	30,624	27,639	99,611
Supplemental pro forma net income (loss)				$ 87,375

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Business acquisitions pro forma net income including adjustment of acquisition related costs.

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Business acquisitions pro forma net Income loss excluding adjustment of acquisition related costs.

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