Condensed Consolidating Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
ASSETS
Cash and cash equivalents	$ 70,094	$ 62,804
Accounts receivable, net of allowance	220,037	247,084
Deferred tax assets	5,174	8,022
Prepaid expenses and other current assets	27,434	26,383
Current assets of discontinued operations	541	6,449
Total current assets	323,280	350,742
Property and equipment, net	2,546,904	2,566,482
Restricted cash	5,835	5,022
Investment in direct financing lease	5,994	7,467
Goodwill	17,229	11,158
Other assets	65,956	30,701
Non-current deferred tax assets	2,959
Non-current assets of discontinued operations	25	3,170
Total assets	2,968,182	2,974,742
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	228,296	164,529
Income taxes payable	964	102
Current liabilities of discontinued operations	1,066	1,827
Total current liabilities	230,326	166,458
Long-term debt	1,185,000	1,111,545
Deferred tax liabilities		139,526
Other liabilities	45,908	35,593
Total liabilities	1,461,234	1,453,122
Total stockholders' equity	1,506,948	1,521,620	1,492,078	1,408,022
Total liabilities and stockholders' equity	2,968,182	2,974,742
Parent
ASSETS
Cash and cash equivalents	51,008
Accounts receivable, net of allowance	178,973	136,128
Deferred tax assets	7	137
Prepaid expenses and other current assets	7,357	1,766
Total current assets	237,345	138,031
Property and equipment, net	2,450,227	2,462,917
Restricted cash	811
Investment in direct financing lease	5,994	7,467
Other assets	237,017	191,502
Total assets	2,931,394	2,799,917
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	237,726	28,061
Total current liabilities	237,726	28,061
Long-term debt	1,185,000	1,111,545
Deferred tax liabilities	557	138,691
Other liabilities	1,163
Total liabilities	1,424,446	1,278,297
Total stockholders' equity	1,506,948	1,521,620
Total liabilities and stockholders' equity	2,931,394	2,799,917
Combined Subsidiary Guarantors
ASSETS
Cash and cash equivalents	19,086	62,804
Accounts receivable, net of allowance	175,227	249,512
Deferred tax assets	5,167	7,885
Prepaid expenses and other current assets	29,596	34,499
Current assets of discontinued operations	541	6,449
Total current assets	229,617	361,149
Property and equipment, net	96,677	103,565
Restricted cash	5,024	5,022
Goodwill	17,229	11,158
Other assets	44,459	114,922
Non-current deferred tax assets	3,516
Non-current assets of discontinued operations	25	3,170
Total assets	396,547	598,986
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	134,218	284,871
Income taxes payable	964	102
Current liabilities of discontinued operations	1,066	1,827
Total current liabilities	136,248	286,800
Long-term debt	115,000	100,000
Deferred tax liabilities		835
Other liabilities	44,745	35,593
Total liabilities	295,993	423,228
Total stockholders' equity	100,554	175,758
Total liabilities and stockholders' equity	396,547	598,986
Consolidating Adjustments and Other
ASSETS
Accounts receivable, net of allowance	(134,163)	(138,556)
Prepaid expenses and other current assets	(9,519)	(9,882)
Total current assets	(143,682)	(148,438)
Other assets	(215,520)	(275,723)
Non-current deferred tax assets	(557)
Total assets	(359,759)	(424,161)
LIABILITIES AND STOCKHOLDERS' EQUITY
Accounts payable and accrued expenses	(143,648)	(148,403)
Total current liabilities	(143,648)	(148,403)
Long-term debt	(115,000)	(100,000)
Deferred tax liabilities	(557)
Total liabilities	(259,205)	(248,403)
Total stockholders' equity	(100,554)	(175,758)
Total liabilities and stockholders' equity	$ (359,759)	$ (424,161)