Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The net amount of operating interest income (expense).

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended								12 Months Ended
SEGMENT INFORMATION (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)
SEGMENT INFORMATION
Number of operating segments \| segment									3	3
Number of reportable segments \| segment									3	3
Assets	$ 1,356,368				$ 405,066				$ 1,356,368	$ 405,066
Segment information
Revenue	304,237	$ 153,880	$ 134,449	$ 99,925	86,734	$ 73,907	$ 62,919	$ 78,839	692,491	302,399	$ 535,577
Income (loss) before taxes									(35,978)	(314,472)	(81,569)
Depreciation and amortization									103,449	97,107	107,712
Capital Expenditures									108,277	36,326	48,686
Loss from operations	(8,039)	$ 2,457	$ (11,909)	$ (12,508)	(21,334)	$ (31,266)	$ (224,822)	$ (21,551)	(29,999)	(298,973)	(68,773)
Other income, net									369	629	893
Water Solutions
SEGMENT INFORMATION
Assets	994,159				324,171				994,159	324,171
Segment information
Revenue									528,997	241,766	427,592
Income (loss) before taxes									17,424	(282,019)	(52,757)
Depreciation and amortization									82,056	81,051	89,271
Capital Expenditures									87,123	34,458	34,724
Oilfield Chemicals
SEGMENT INFORMATION
Assets	186,333								186,333
Segment information
Revenue									41,586
Income (loss) before taxes									663
Depreciation and amortization									2,040
Capital Expenditures									3,063
Wellsite Services
SEGMENT INFORMATION
Assets	151,272				68,868				151,272	68,868
Segment information
Revenue									123,964	61,461	109,976
Income (loss) before taxes									(6,527)	(15,038)	(3,489)
Depreciation and amortization									17,550	16,056	18,177
Capital Expenditures									18,091	1,868	13,962
Elimination
Segment information
Revenue									(2,056)	(828)	(1,991)
Corporate
SEGMENT INFORMATION
Assets	$ 24,604				$ 12,027				24,604	12,027
Segment information
Income (loss) before taxes									(41,559)	(1,916)	(12,527)
Depreciation and amortization									1,803		264
Material reconciling items
Segment information
Loss from operations									11,560	(297,057)	(56,246)
Interest expense, net									(6,629)	(16,128)	(13,689)
Other income, net									$ 650	$ 629	$ 893