GOODWILL AND INTANGIBLE ASSETS - Components of Intangible Assets (Detail) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 33,665	$ 33,331
Less accumulated amortization		(25,969)	(24,079)
Intangible assets, net		7,696	9,252
Intangible amortization expenses	$ 1,974	2,141	2,567	$ 2,556
Covenants Not-to-Compete
Finite-Lived Intangible Assets [Line Items]
Intangible assets		17,594	17,266
Less accumulated amortization		(16,402)	(16,198)
Intangible assets, net		1,192	1,068
Client Lists
Finite-Lived Intangible Assets [Line Items]
Intangible assets		16,071	16,065
Less accumulated amortization		(9,567)	(7,881)
Intangible assets, net		$ 6,504	$ 8,184