FAIR VALUE MEASUREMENTS - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset		$ 693		$ 693		$ 515
Cash received on settled hedge	$ 8,800			8,833	$ 0
Settlement of hedge, amount recognized in accumulated other comprehensive income	5,300	646	$ (149)	(3,778)	(149)
Settlement of hedge, tax amount recognized in accumulated other comprehensive income	$ 3,500	117	$ 55	2,498	$ 55
Contingent consideration liabilities		26,890		26,890		19,941
Debt obligations, carrying amount		1,668,006		1,668,006		1,659,215
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Maximum contingent liability if financial performance measures were fully met		29,800		29,800
Level 3 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset		0		0		0
Contingent consideration liabilities		26,890		26,890		19,941
Level 3 Inputs [Member] | Current Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent consideration liabilities		15,400		15,400
Level 2 Inputs [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative asset		693		693		515
Contingent consideration liabilities		0		0		0
Debt obligations, fair value		$ 1,670,000		$ 1,670,000		$ 1,670,000