ACQUISITIONS - Aggregate Purchase Price Paid for Acquisitions and Other Adjustments to Consideration (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Combinations [Abstract]
Cash	$ 2,419,437	$ 374,321	$ 161,936
Promissory notes	64,072	125,229	64,581
Deferred consideration	3,172	3,535	31,149
Contingent consideration	12,945	17,174	4,371
Total purchase price	$ 2,499,626	$ 520,259	$ 262,037