Condensed Consolidating Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 48,847	$ 77,909
Accounts receivable, net of allowance	292,466	244,957
Current deferred tax assets	11,430	9,241
Prepaid expenses and other current assets	26,925	20,612
Assets held for sale	4,145
Current assets of discontinued operations		15
Total current assets	383,813	352,734
Property and equipment, net	2,614,264	2,546,613
Restricted cash	2,707	5,589
Investment in direct financing lease	3,811	5,473
Goodwill	16,110	16,110
Non-current deferred tax assets	4,537	3,078
Other assets	75,908	77,828
Total assets	3,101,150	3,007,425
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	247,762	252,277
Income taxes payable	889	1,243
Current liabilities of discontinued operations	53	886
Total current liabilities	248,704	254,406
Long-term debt	1,240,000	1,205,000
Other liabilities	110,153	45,512
Total liabilities	1,598,857	1,504,918
Total stockholders' equity	1,502,293	1,502,507	1,506,948	1,521,620
Total liabilities and stockholders' equity	3,101,150	3,007,425
Parent
ASSETS
Cash and cash equivalents	10,334	31,647
Accounts receivable, net of allowance	184,445	203,018
Current deferred tax assets		2
Prepaid expenses and other current assets	74,107	7,580
Assets held for sale	4,145
Total current assets	273,031	242,247
Property and equipment, net	2,458,764	2,450,028
Restricted cash	1,116	1,016
Investment in direct financing lease	3,811	5,473
Other assets	261,040	245,028
Total assets	2,997,762	2,943,792
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	253,266	234,277
Income taxes payable	84
Current deferred tax liabilities	13
Total current liabilities	253,363	234,277
Long-term debt	1,240,000	1,205,000
Deferred tax liabilities	518	555
Other liabilities	1,588	1,453
Total liabilities	1,495,469	1,441,285
Total stockholders' equity	1,502,293	1,502,507
Total liabilities and stockholders' equity	2,997,762	2,943,792
Combined Subsidiary Guarantors
ASSETS
Cash and cash equivalents	38,513	46,262
Accounts receivable, net of allowance	240,877	178,894
Current deferred tax assets	11,443	9,239
Prepaid expenses and other current assets	31,423	22,856
Current assets of discontinued operations		15
Total current assets	322,256	257,266
Property and equipment, net	155,500	96,585
Restricted cash	1,591	4,573
Goodwill	16,110	16,110
Non-current deferred tax assets	5,055	3,633
Other assets	47,451	45,149
Total assets	547,963	423,316
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	135,422	164,745
Income taxes payable	805	1,243
Note payable to an affiliate	70,500
Current liabilities of discontinued operations	53	886
Total current liabilities	206,780	166,874
Long-term debt	115,000	115,000
Other liabilities	108,565	44,059
Total liabilities	430,345	325,933
Total stockholders' equity	117,618	97,383
Total liabilities and stockholders' equity	547,963	423,316
Consolidating Adjustments and Other
ASSETS
Accounts receivable, net of allowance	(132,856)	(136,955)
Current deferred tax assets	(13)
Prepaid expenses and other current assets	(78,605)	(9,824)
Total current assets	(211,474)	(146,779)
Non-current deferred tax assets	(518)	(555)
Other assets	(232,583)	(212,349)
Total assets	(444,575)	(359,683)
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	(140,926)	(146,745)
Current deferred tax liabilities	(13)
Note payable to an affiliate	(70,500)
Total current liabilities	(211,439)	(146,745)
Long-term debt	(115,000)	(115,000)
Deferred tax liabilities	(518)	(555)
Total liabilities	(326,957)	(262,300)
Total stockholders' equity	(117,618)	(97,383)
Total liabilities and stockholders' equity	$ (444,575)	$ (359,683)