NONCONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Effects of changes in noncontrolling interests on equity
Net loss attributable to Select Energy Services, Inc. and its Predecessor	$ 1,224	$ (7,164)	$ (285,359)
Transfers from noncontrolling interests:
Increase in additional paid-in capital as a result of the contribution of proceeds from the IPO to SEC holdings, LLC in exchange for common units		87,835
Increase in additional paid-in capital as a result of the cotribution of assets acquired to SES Holdings, LLC in exchange for common units		4,360
Increase in contributed capital due to purchase of noncontrolling interest			135
Change to equity from net loss attributable to Select Energy Services, Inc. and its Predecessor and transfers from noncontrollig interests		$ 85,031	$ (285,224)

This element represents the total net income attributable to the parent for the period and the effect of net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not result in a deconsolidation of the subsidiary from the consolidated financial statements.

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Represents a sale (new stock issuance) by a subsidiary to noncontrolling interests (third parties, parties directly or indirectly unrelated to parent) during the period. The capital transaction by subsidiary does not result in a loss of control by the parent, but does effect a change in total (consolidated) equity attributable to the parent.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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