Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 86,939	$ 13,861
Accounts and notes receivable, net of allowance of $571 and $476 as of December 31, 2013 and 2012, respectively	58,274	45,135
Inventory, net	5,302	4,389
Restricted cash	14,896	8,298
Current portion of deferred tax asset, net	21,202	13,086
Prepaid expenses, deferred costs, and other current assets	20,159	30,980
Total current assets	206,772	115,749
Property and equipment, net	270,966	236,238
Intangible assets, net	161,615	102,573
Goodwill	404,491	285,696
Deferred tax asset, net	9,680	26,468
Prepaid expenses, deferred costs, and other noncurrent assets	2,679	2,168
Total assets	1,056,203	768,892
Current liabilities:
Current portion of long-term debt and notes payable	1,289	1,467
Current portion of other long-term liabilities	35,597	27,220
Accounts payable	38,981	21,593
Accrued liabilities	137,776	80,112
Current portion of deferred tax liability, net	1,152	1,179
Total current liabilities	214,795	131,571
Long-term liabilities:
Long-term debt	489,225	353,352
Asset retirement obligation	60,665	41,862
Deferred tax liability, net	5,668	182
Other long-term liabilities	38,736	93,121
Total liabilities	809,089	620,088
Commitments and contingencies
Stockholders' equity:
Common stock, $0.0001 par value; 125,000,000 shares authorized; 51,207,849 and 50,569,875 shares issued as of December 31, 2013 and 2012, respectively; 44,375,952 and 44,641,224 shares outstanding as of December 31, 2013 and 2012, respectively	5	5
Additional paid-in capital	330,862	252,956
Accumulated other comprehensive loss, net	(72,954)	(105,085)
Retained earnings	81,677	57,861
Treasury stock; 6,831,897 and 5,928,651 shares at cost as of December 31, 2013 and 2012, respectively	(90,679)	(58,270)
Total parent stockholders' equity	248,911	147,467
Noncontrolling interests	(1,797)	1,337
Total stockholders' equity	247,114	148,804
Total liabilities and stockholders' equity	$ 1,056,203	$ 768,892