GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014
Changes in goodwill
Balance at the beginning of the period			$ 217,609
Impairment charges	$ (6,700)		(6,700)
Foreign Currency Translation			(1,243)
Balance at the end of the period	209,666		209,666
Intangible Assets
Amortizing intangible assets, Cost	238,524		238,524			$ 240,905
Accumulated amortization	(18,396)		(18,396)			(12,135)
Amortizing intangible assets, Net	220,128		220,128			228,770
Total intangible assets, cost	288,407		288,407			290,802
Total intangible assets, net	270,011		270,011			278,667
Amortization expense	3,304	$ 862	6,606	$ 1,215
Permits and licenses
Intangible Assets
Nonamortizing intangible assets	49,750		49,750			49,750
Tradename
Intangible Assets
Nonamortizing intangible assets	133		133			147
Allstate | Forecast
Changes in goodwill
Cash consideration					$ 58,000
Allstate | Forecast | Subsequent event
Changes in goodwill
Cash consideration					$ 58,000
Permits, licenses and lease
Intangible Assets
Amortizing intangible assets, Cost	112,090		112,090			113,693
Accumulated amortization	(5,688)		(5,688)			(4,427)
Amortizing intangible assets, Net	106,402		106,402			109,266
Customer relationships
Intangible Assets
Amortizing intangible assets, Cost	102,852		102,852			103,086
Accumulated amortization	(7,840)		(7,840)			(4,488)
Amortizing intangible assets, Net	95,012		95,012			98,598
Technology - formulae and processes
Intangible Assets
Amortizing intangible assets, Cost	7,322		7,322			7,844
Accumulated amortization	(1,059)		(1,059)			(1,009)
Amortizing intangible assets, Net	6,263		6,263			6,835
Customer backlog
Intangible Assets
Amortizing intangible assets, Cost	4,600		4,600			4,600
Accumulated amortization	(476)		(476)			(246)
Amortizing intangible assets, Net	4,124		4,124			4,354
Tradename
Intangible Assets
Amortizing intangible assets, Cost	5,485		5,485			5,481
Accumulated amortization	(1,892)		(1,892)			(979)
Amortizing intangible assets, Net	3,593		3,593			4,502
Developed software
Intangible Assets
Amortizing intangible assets, Cost	3,725		3,725			3,745
Accumulated amortization	(629)		(629)			(428)
Amortizing intangible assets, Net	3,096		3,096			3,317
Non-compete agreements
Intangible Assets
Amortizing intangible assets, Cost	920		920			920
Accumulated amortization	(671)		(671)			(462)
Amortizing intangible assets, Net	249		249			458
Internet domain and website
Intangible Assets
Amortizing intangible assets, Cost	869		869			869
Accumulated amortization	(47)		(47)			(24)
Amortizing intangible assets, Net	822		822			845
Database
Intangible Assets
Amortizing intangible assets, Cost	661		661			667
Accumulated amortization	(94)		(94)			(72)
Amortizing intangible assets, Net	567		567			$ 595
Environmental Services
Changes in goodwill
Balance at the beginning of the period			152,396
Foreign Currency Translation			(1,243)
Balance at the end of the period	151,153		151,153
Field & Industrial Services
Changes in goodwill
Balance at the beginning of the period			65,213
Impairment charges	(6,700)		(6,700)
Balance at the end of the period	$ 58,513		$ 58,513
Goodwill impairment charge per diluted share	$ 0.31