Basis of Preparation and Presentation (Narrative) (Details)	9 Months Ended
Sep. 30, 2019
Basis of Preparation and Presentation [Abstract]
Methodology for Determining Whether Entity is Primary Beneficiary	We consolidate the activities of Superior Pipeline Company, L.L.C. (Superior), a 50/50 joint venture between Unit Corporation and SP Investor Holdings, LLC, which qualifies as a Variable Interest Entity (VIE) under generally accepted accounting principles in the United States (GAAP). We have concluded that we are the primary beneficiary of the VIE, as defined in the accounting standards, since we have the power to direct those activities that most significantly affect the economic performance of Superior as further described in Note 15 - Variable Interest Entity Arrangements.

Description of significant judgments and assumptions made by a reporting entity in determining whether it must: (1) consolidate a Variable Interest Entity (VIE) or (2) disclose information about its involvement in a VIE, and may include discussion of the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance is shared among multiple parties such that no one party is the primary beneficiary (as defined) or information about the types of involvements the reporting entity considers significant, supplemented with information about how the significant involvements were considered in determining whether the reporting entity is the primary beneficiary.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=SL6759159-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 2AA
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=SL6759068-111685

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5728-111685

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