UNAUDITED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Service revenues	$ 702,033	$ 503,728	$ 2,048,527	$ 1,523,767
Product revenues	205,502	30,078	581,699	105,179
Total revenues	907,535	533,806	2,630,226	1,628,946
Cost of revenues (exclusive of items shown separately below)
Service revenues	478,434	348,758	1,402,409	1,056,174
Product revenues	168,685	24,182	495,060	84,704
Total cost of revenues	647,119	372,940	1,897,469	1,140,878
Selling, general and administrative expenses	114,464	60,339	365,546	197,892
Accretion of environmental liabilities	2,914	2,488	8,628	7,409
Depreciation and amortization	69,430	41,300	196,904	116,794
Income from operations	73,608	56,739	161,679	165,973
Other (expense) income	(150)	(91)	2,030	(465)
Loss on early extinguishment of debt	0	(26,385)	0	(26,385)
Interest expense, net of interest income of $96 and $362 for the quarter and year-to-date ended 2013 and $221 and $623 for the quarter and year-to-date ended 2012, respectively	(19,326)	(11,596)	(58,784)	(33,836)
Income before provision for income taxes	54,132	18,667	104,925	105,287
Provision for income taxes	18,771	6,308	36,160	37,487
Net income	$ 35,361	$ 12,359	$ 68,765	$ 67,800
Earnings per share:
Basic (in USD per share)	$ 0.58	$ 0.23	$ 1.14	$ 1.27
Diluted (in USD per share)	$ 0.58	$ 0.23	$ 1.13	$ 1.27
Weighted average common shares outstanding - basic (in shares)	60,610	53,374	60,542	53,303
Weighted average common shares outstanding - diluted (in shares)	60,760	53,565	60,692	53,519