GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes to Goodwill

The changes in goodwill for the years ended December 31, 2016 and 2015 were as follows (in thousands):

	Technical Services			Industrial and Field Services			Safety-Kleen			Oil, Gas and Lodging Services			Totals
Balance at January 1, 2015	$	50,092		$	109,214		$	224,756		$	68,607		$	452,669
Increase from current period acquisitions	—			—			46,539			—			46,539
Measurement period adjustments from prior period acquisitions	—			—			—			3,574			3,574
Goodwill impairment charge	—			—			—			(31,992		)	(31,992		)
Foreign currency translation and other	(825		)	(3,928		)	(4,951		)	(7,981		)	(17,685		)
Balance at December 31, 2015	$	49,267		$	105,286		$	266,344		$	32,208		$	453,105
Increase from current period acquisitions	12,572			6,953			26,266			—			45,791
Measurement period adjustments from prior period acquisitions	—			—			2,095			—			2,095
Decrease from disposition of business	—			(4,994		)	—			—			(4,994		)
Goodwill impairment charge	—			—			—			(34,013		)	(34,013		)
Foreign currency translation and other	(723		)	723			1,365			1,805			3,170
Balance at December 31, 2016	$	61,116		$	107,968		$	296,070		$	—		$	465,154

Schedule of Finite-Lived Intangible Assets by Major Class

As of December 31, 2016 and 2015, the Company's finite-lived and indefinite lived intangible assets consisted of the following (in thousands):

	December 31, 2016							December 31, 2015
	Cost		Accumulated Amortization		Net		Weighted Average Amortization Period (in years)	Cost		Accumulated Amortization		Net		Weighted Average Amortization Period (in years)
Permits	$	171,637	$	67,301	$	104,336	18.9	$	161,396	$	61,142	$	100,254	19.0
Customer and supplier relationships	393,426		127,462		265,964		12.2	374,866		99,463		275,403		10.1
Other intangible    assets	34,254		28,456		5,798		7.1	31,416		22,581		8,835		1.5
Total amortizable permits and other intangible assets	599,317		223,219		376,098		13.9	567,678		183,186		384,492		10.0
Trademarks and trade     names	122,623		—		122,623		Indefinite	122,326		—		122,326		Indefinite
Total permits and other intangible assets	$	721,940	$	223,219	$	498,721		$	690,004	$	183,186	$	506,818

Schedule of Indefinite-Lived Intangible Assets

As of December 31, 2016 and 2015, the Company's finite-lived and indefinite lived intangible assets consisted of the following (in thousands):

	December 31, 2016							December 31, 2015
	Cost		Accumulated Amortization		Net		Weighted Average Amortization Period (in years)	Cost		Accumulated Amortization		Net		Weighted Average Amortization Period (in years)
Permits	$	171,637	$	67,301	$	104,336	18.9	$	161,396	$	61,142	$	100,254	19.0
Customer and supplier relationships	393,426		127,462		265,964		12.2	374,866		99,463		275,403		10.1
Other intangible    assets	34,254		28,456		5,798		7.1	31,416		22,581		8,835		1.5
Total amortizable permits and other intangible assets	599,317		223,219		376,098		13.9	567,678		183,186		384,492		10.0
Trademarks and trade     names	122,623		—		122,623		Indefinite	122,326		—		122,326		Indefinite
Total permits and other intangible assets	$	721,940	$	223,219	$	498,721		$	690,004	$	183,186	$	506,818

Schedule of Expected Amortization for the Net Carrying Amount of Finite Lived Intangible Assets

The expected amortization of the net carrying amount of finite-lived intangible assets at December 31, 2016 is as follows (in thousands):

Years Ending December 31,	Expected Amortization
2017	$	36,904
2018	33,981
2019	31,272
2020	29,087
2021	26,515
Thereafter	218,339
	$	376,098