CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue
Water solutions and related services	$ 281,555	$ 78,377
Accommodations and rentals	14,744	9,515
Wellsite completion and construction services	16,466	12,033
Oilfield chemical product sales	63,630
Total revenue	376,395	99,925
Costs of revenue
Water solutions and related services	215,425	60,621
Accommodations and rentals	10,665	7,923
Wellsite completion and construction services	14,390	10,419
Oilfield chemical product sales	57,084
Depreciation and amortization	30,882	21,204
Total costs of revenue	328,446	100,167
Gross profit (loss)	47,949	(242)
Operating expenses
Selling, general and administrative	25,681	9,957
Depreciation and amortization	541	446
Impairment of investment	2,000
Lease abandonment costs	1,124	1,863
Total operating expenses	29,346	12,266
Income (loss) from operations	18,603	(12,508)
Other income (expense)
Interest expense, net	(1,151)	(730)
Foreign currency losses, net	(400)
Other (expense) income, net	(458)	1,064
Income (loss) before tax expense	16,594	(12,174)
Tax expense	(462)	(106)
Net income (loss)	16,132	(12,280)
Less: net (income) loss attributable to noncontrolling interests	(6,033)	8,108
Net income (loss) attributable to Select Energy Services, Inc.	10,099	(4,172)
EARNINGS PER SHARE
Allocation of net income (loss) attributable to, Diluted	10,134
Class A Common Stock
Other income (expense)
Net income (loss) attributable to Select Energy Services, Inc.	9,097	$ (809)
EARNINGS PER SHARE
Allocation of net income (loss) attributable to, Diluted	$ 9,137
Weighted average shares outstanding, basic	59,064,958
Net income (loss) per share attributable to common stockholders, basis	$ 0.15	$ (0.21)
Weighted average shares outstanding, diluted	59,673,466
Net income (loss) per share attributable to common stockholders, diluted	$ 0.15	$ (0.21)
Weighted-average shares of common stock outstanding — basic & diluted		3,870,194
Net loss per share attributable to common stockholders:		$ (0.21)
Class A-1 Common Stock
EARNINGS PER SHARE
Net income (loss) per share attributable to common stockholders, basis		(0.21)
Net income (loss) per share attributable to common stockholders, diluted		$ (0.21)
Class A-2 Common Stock
Other income (expense)
Net income (loss) attributable to Select Energy Services, Inc.	$ 1,002	$ (3,363)
EARNINGS PER SHARE
Allocation of net income (loss) attributable to, Diluted	$ 997
Weighted average shares outstanding, basic	6,507,445
Net income (loss) per share attributable to common stockholders, basis	$ 0.15
Weighted average shares outstanding, diluted	6,507,445
Net income (loss) per share attributable to common stockholders, diluted	$ 0.15
Weighted-average shares of common stock outstanding — basic & diluted		16,100,000
Net loss per share attributable to common stockholders:		$ (0.21)
Class B Common Stock
EARNINGS PER SHARE
Weighted average shares outstanding, basic	40,331,989
Weighted average shares outstanding, diluted	40,331,989
Weighted-average shares of common stock outstanding — basic & diluted		38,462,541