Goodwill And Intangible Assets (Changes In Goodwill) (Details) (USD $) In Thousands	6 Months Ended		3 Months Ended		3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011 Mideast Group [Member]	Dec. 31, 2010 Mideast Group [Member]	Jun. 30, 2011 Southeast Group [Member]	Jun. 30, 2011 Southeast Group [Member]	Jun. 30, 2011 West Group [Member]	Jun. 30, 2011 West Group [Member]
Goodwill, Beginning Balance	$ 626,527	$ 624,224	$ 122,052	$ 122,052	$ 105,870	$ 105,870	$ 398,605	$ 398,605
Acquisitions	12,232						12,232	12,232
Goodwill, Ending Balance	$ 638,759	$ 624,224	$ 122,052	$ 122,052	$ 105,870	$ 105,870	$ 410,837	$ 410,837

Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43

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