GOODWILL AND OTHER INTANGIBLE ASSETS - Values of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	$ 1,024,567	$ 808,133
Accumulated Amortization	114,922	88,098
Net Value	909,645	720,035
Amortizable intangibles | Covenants not-to-compete
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	8,474	9,405
Accumulated Amortization	5,688	5,366
Net Value	2,786	4,039
Amortizable intangibles | Customer relationships
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	755,148	670,889
Accumulated Amortization	107,365	81,271
Net Value	647,783	589,618
Amortizable intangibles | Trade names
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	6,062	5,283
Accumulated Amortization	1,313	1,031
Net Value	4,749	4,252
Amortizable intangibles | Technology
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	611	611
Accumulated Amortization	521	416
Net Value	90	195
Amortizable intangibles | Other
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	539	91
Accumulated Amortization	35	14
Net Value	504	77
Indefinite lived intangibles | Operating permits
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	247,933	116,054
Net Value	247,933	116,054
Indefinite lived intangibles | Trade names
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	5,800	5,800
Net Value	$ 5,800	$ 5,800