Supplemental Guarantor Financial Information (Condensed Consolidating Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	$ 61,364	$ 86,939	$ 22,341	$ 13,861
Accounts and notes receivable, net	62,866	58,274
Current portion of deferred tax asset, net	20,397	21,202
Other current assets	64,693	40,357
Total current assets	209,320	206,772
Property and equipment, net	284,167	270,966
Intangible assets, net	145,254	155,276
Goodwill	412,964	404,491
Deferred tax asset, net	12,119	9,680
Prepaid expenses, deferred costs, and other noncurrent assets	7,716	9,018
Total assets	1,071,540	1,056,203
Current portion of long-term debt	615	1,289
Current portion of other long-term liabilities	36,555	35,597
Accounts payable and accrued liabilities	171,323	176,757
Current portion of deferred tax liability, net		1,152
Total current liabilities	208,493	214,795
Long-term debt	473,613	489,225
Asset retirement obligation, excluding current portion	64,881	60,665
Deferred tax liability, net	5,555	5,668
Other long-term liabilities	42,392	38,736
Total liabilities	794,934	809,089
Stockholders' equity	276,606	247,114
Total liabilities and stockholders' equity	1,071,540	1,056,203
Elimination [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Accounts and notes receivable, net	(70,984)	(134,432)
Other current assets	(281)	(88)
Total current assets	(71,265)	(134,520)
Property and equipment, net	(610)	(431)
Investments in and advances to subsidiaries	(760,541)	(691,303)
Intercompany receivable	(254,594)	(194,855)
Total assets	(1,087,010)	(1,021,109)
Accounts payable and accrued liabilities	(71,362)	(134,029)
Total current liabilities	(71,362)	(134,029)
Intercompany payable	(307,466)	(247,726)
Total liabilities	(378,828)	(381,755)
Stockholders' equity	(708,182)	(639,354)
Total liabilities and stockholders' equity	(1,087,010)	(1,021,109)
Parent [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	6	412	21	5
Accounts and notes receivable, net	66,603	130,835
Current portion of deferred tax asset, net	15,673	15,735
Other current assets	471	917
Total current assets	82,753	147,899
Intangible assets, net	9,706	9,466
Investments in and advances to subsidiaries	514,556	445,318
Intercompany receivable	154,041	150,890
Total assets	761,056	753,573
Accounts payable and accrued liabilities	8,282	12,953
Total current liabilities	8,282	12,953
Long-term debt	473,613	489,182
Deferred tax liability, net	2,555	4,324
Total liabilities	484,450	506,459
Stockholders' equity	276,606	247,114
Total liabilities and stockholders' equity	761,056	753,573
Guarantors [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	49,598	73,379	18,170	10,674
Accounts and notes receivable, net	46,538	43,929
Current portion of deferred tax asset, net	1,915	1,915
Other current assets	23,158	11,580
Total current assets	121,209	130,803
Property and equipment, net	170,259	166,909
Intangible assets, net	69,605	75,975
Goodwill	293,888	288,439
Investments in and advances to subsidiaries	245,985	245,985
Intercompany receivable	100,553	43,965
Prepaid expenses, deferred costs, and other noncurrent assets	2,985	3,593
Total assets	1,004,484	955,669
Current portion of other long-term liabilities	34,357	34,009
Accounts payable and accrued liabilities	151,636	213,128
Total current liabilities	185,993	247,137
Long-term debt		3
Intercompany payable	190,234	148,306
Asset retirement obligation, excluding current portion	22,615	21,517
Deferred tax liability, net	605	526
Other long-term liabilities	39,925	38,681
Total liabilities	439,372	456,170
Stockholders' equity	565,112	499,499
Total liabilities and stockholders' equity	1,004,484	955,669
Non-Guarantors [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	11,760	13,148	4,150	3,182
Accounts and notes receivable, net	20,709	17,942
Current portion of deferred tax asset, net	2,809	3,552
Other current assets	41,345	27,948
Total current assets	76,623	62,590
Property and equipment, net	114,518	104,488
Intangible assets, net	65,943	69,835
Goodwill	119,076	116,052
Deferred tax asset, net	12,119	9,680
Prepaid expenses, deferred costs, and other noncurrent assets	4,731	5,425
Total assets	393,010	368,070
Current portion of long-term debt	615	1,289
Current portion of other long-term liabilities	2,198	1,588
Accounts payable and accrued liabilities	82,767	84,705
Current portion of deferred tax liability, net		1,152
Total current liabilities	85,580	88,734
Long-term debt		40
Intercompany payable	117,232	99,420
Asset retirement obligation, excluding current portion	42,266	39,148
Deferred tax liability, net	2,395	818
Other long-term liabilities	2,467	55
Total liabilities	249,940	228,215
Stockholders' equity	143,070	139,855
Total liabilities and stockholders' equity	$ 393,010	$ 368,070