Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow to settle outstanding phantom units.

+ References

No definition available.

+ Details

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Namespace Prefix:	wttr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the distribution amount per award under the plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	wttr_
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EQUITY BASED COMPENSATION - Phantom Awards (Details4) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	May 05, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 31, 2017
EQUITY-BASED COMPENSATION
Settlement of phantom units	$ 7.8
Share price		$ 20.00	$ 6.08
Outstanding units		299,801			331,854
Phantom Awards
EQUITY-BASED COMPENSATION
Settlement of phantom units	$ 7.8
Share price	$ 14.00
Cash payment amount per award	$ 5.53
Compensation expense		$ 7.8	$ 0.0	$ 0.0
Outstanding units		0