Acquisitions (Consolidated Income Statement Information) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Acquisitions [Abstract]
Revenues	$ 435,510	$ 406,201	$ 1,261,734	$ 1,158,956
Pro Forma Adjustments Revenues		9,027		36,483
Pro Forma Revenues		415,228		1,195,439
Net income	110,240	56,637	303,304	223,623
Pro Forma Adjustments Net income		4,790		15,740
Pro Forma Net income		$ 61,427		$ 239,363

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details