NONCONTROLLING INTERESTS - Effect of Changes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Effects of changes in noncontrolling interests on equity
Net income (loss) attributable to Select Energy Services, Inc.	$ 12,503	$ (16,567)	$ 19,305	$ (39,674)
Transfers from (to) noncontrolling interests:
Noncontrolling interest in subsidiary				1,074
Decrease in additional paid-in capital as a result of issuing shares for business combinations			(1,356)
Decrease in additional paid-in capital as a result of stock option exercises			(24)
Increase in additional paid-in capital as a result of restricted stock issuance, net of forfeitures			2,188	1,582
Increase (decrease) in additional paid-in capital as a result of the repurchase of SES Holdings LLC Units			436	(19)
(Decrease) increase in additional paid-in capital as a result of the Employee Stock Purchase Plan shares issued			(1)	1
Change to equity from net income (loss) attributable to Select Energy Services, Inc. and transfers from noncontrolling interests			$ 20,548	(38,110)
SES Holdings LLC [Member]
Transfers from (to) noncontrolling interests:
Noncontrolling interest in subsidiary				$ 900