Goodwill and Other Intangible Assets, net - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill
Goodwill, Beginning Balance	$ 34,180
Goodwill, Ending Balance	41,038	$ 34,180
Permian Basin \| Permian Basin
Goodwill
Goodwill, Beginning Balance	34,180	8,065
Goodwill, Ending Balance	41,038	34,180
Permian Basin \| Permian Basin \| Signor
Goodwill
Goodwill acquired		$ 26,115
Permian Basin \| Permian Basin \| Superior
Goodwill
Goodwill acquired	$ 6,858

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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-SubTopic 20
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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+ References

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