The cash inflow after purchase price adjustments associated with the amount received from the sale of a business segment or subsidiary or sale of an entity that is related to it but not strictly controlled during the period (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

No definition available.

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- 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.

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- Definition

Amount of gain (loss) on sale or disposal of proven and unproven oil and gas properties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The cash inflow associated with the amount received from the sale of a business segment or subsidiary or sale of an entity that is related to it but not strictly controlled during the period (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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Acquisitions and Divestitures (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended
	Apr. 30, 2018	Oct. 31, 2017	May 31, 2017	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Oklahoma Production Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture			$ 5.5
Gain on sale						$ 2.4
Briggs Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture	$ 4.5
Proceeds from divestiture after purchase price adjustments	4.0
Gain on sale				$ 1.6
Texas Production Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture		$ 6.3
Gain on sale					$ 1.4
Cola Divestiture
Business Acquisition [Line Items]
Proceeds from divestiture	$ 1.0
Gain on sale				$ 1.1