Financial Information for the Company and Its Subsidiaries - Summary of Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 30,716	$ 11,215	$ 34,572	$ 94,040
Accounts receivable, net	285,132	216,626
Other current assets	76,519	66,895
Total current assets	392,367	294,736
Property and equipment, net	3,274,540	1,709,053
Goodwill	2,832,201	2,128,215
Intangible assets, net	84,996	59,575
Deferred tax assets - noncurrent	17,929	49,114
Derivative instruments	40,459
Other assets	42,007	38,515
Total assets	6,684,499	4,279,208
Current liabilities:
Current portion of long-term debt	73,410	45,360
Accounts payable	108,211	91,341
Accrued salaries and benefits	113,392	80,696
Other accrued liabilities	124,788	72,806
Total current liabilities	419,801	290,203
Long-term debt	3,578,383	2,195,384
Deferred tax liabilities - noncurrent	85,526	23,936
Other liabilities	151,628	78,602
Total liabilities	4,235,338	2,588,125
Redeemable noncontrolling interests	12,881	8,055
Total equity	2,436,280	1,683,028
Total liabilities and equity	6,684,499	4,279,208
Consolidating Adjustments [Member]
Current assets:
Other current assets	(3,795)
Total current assets	(3,795)
Investment in subsidiaries	(5,210,634)	(3,495,067)
Other assets	(843,194)	(424,024)
Total assets	(6,057,623)	(3,919,091)
Current liabilities:
Other accrued liabilities	(3,795)
Total current liabilities	(3,795)
Long-term debt	(843,194)	(424,024)
Total liabilities	(846,989)	(424,024)
Total equity	(5,210,634)	(3,495,067)
Total liabilities and equity	(6,057,623)	(3,919,091)
Parent [Member]
Current assets:
Deferred tax assets - noncurrent	3,579	3,946
Derivative instruments	40,459
Investment in subsidiaries	5,210,634	3,495,067
Other assets	845,914	427,270
Total assets	6,100,586	3,926,283
Current liabilities:
Current portion of long-term debt	73,175	45,125
Other accrued liabilities	35,919	26,132
Total current liabilities	109,094	71,257
Long-term debt	3,555,212	2,171,998
Total liabilities	3,664,306	2,243,255
Total equity	2,436,280	1,683,028
Total liabilities and equity	6,100,586	3,926,283
Combined Subsidiary Guarantors [Member]
Current assets:
Cash and cash equivalents	10,048	1,987	17,179	76,685
Accounts receivable, net	209,194	187,546
Other current assets	59,452	57,968
Total current assets	278,694	247,501
Property and equipment, net	907,277	805,439
Goodwill	1,939,361	1,835,339
Intangible assets, net	56,574	57,024
Deferred tax assets - noncurrent	9,671	40,587
Other assets	33,523	32,947
Total assets	3,225,100	3,018,837
Current liabilities:
Accounts payable	68,294	75,015
Accrued salaries and benefits	75,872	66,249
Other accrued liabilities		10,886
Total current liabilities	144,166	152,150
Other liabilities	108,574	75,159
Total liabilities	252,740	227,309
Total equity	2,972,360	2,791,528
Total liabilities and equity	3,225,100	3,018,837
Combined Non-Guarantors [Member]
Current assets:
Cash and cash equivalents	20,668	9,228	$ 17,393	$ 17,355
Accounts receivable, net	75,938	29,080
Other current assets	20,862	8,927
Total current assets	117,468	47,235
Property and equipment, net	2,367,263	903,614
Goodwill	892,840	292,876
Intangible assets, net	28,422	2,551
Deferred tax assets - noncurrent	4,679	4,581
Other assets	5,764	2,322
Total assets	3,416,436	1,253,179
Current liabilities:
Current portion of long-term debt	235	235
Accounts payable	39,917	16,326
Accrued salaries and benefits	37,520	14,447
Other accrued liabilities	92,664	35,788
Total current liabilities	170,336	66,796
Long-term debt	866,365	447,410
Deferred tax liabilities - noncurrent	85,526	23,936
Other liabilities	43,054	3,443
Total liabilities	1,165,281	541,585
Redeemable noncontrolling interests	12,881	8,055
Total equity	2,238,274	703,539
Total liabilities and equity	$ 3,416,436	$ 1,253,179