CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues	$ 533,806	$ 556,053	$ 1,628,946	$ 1,438,250
Cost of revenues (exclusive of items shown separately below)	372,940	386,518	1,140,878	1,006,849
Selling, general and administrative expenses	60,339	65,704	197,892	178,752
Accretion of environmental liabilities	2,488	2,435	7,409	7,231
Depreciation and amortization	41,300	34,604	116,794	87,000
Income from operations	56,739	66,792	165,973	158,418
Other (expense) income	(91)	164	(465)	5,931
Loss on early extinguishment of debt	(26,385)	0	(26,385)	0
Interest expense, net of interest income of $221 and $623, for the quarter and year-to-date ended 2012 and $153 and $700 for the quarter and year-to-date ended 2011, respectively	(11,596)	(10,927)	(33,836)	(28,047)
Income from continuing operations, before provision for income taxes	18,667	56,029	105,287	136,302
Provision for income taxes	6,308	18,896	37,487	47,283
Net Income	$ 12,359	$ 37,133	$ 67,800	$ 89,019
Earnings per share:
Basic (USD Per Share)	$ 0.23	$ 0.70	$ 1.27	$ 1.68
Diluted (USD Per Share)	$ 0.23	$ 0.70	$ 1.27	$ 1.67
Weighted average common shares outstanding - basic (In Shares)	53,374	53,023	53,303	52,921
Weighted average common shares outstanding - diluted (In Shares)	53,565	53,370	53,519	53,298