Oil and Gas Properties - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) $ / Boe	Jun. 30, 2018 USD ($) $ / Boe	Jun. 30, 2019 USD ($) $ / Boe	Jun. 30, 2018 USD ($) $ / Boe
Extractive Industries [Abstract]
Depletion expense	$ 6.6	$ 3.1	$ 11.6	$ 5.4
Average depletion of proved properties (in dollars per Boe) \| $ / Boe	10.74	9.05	10.53	8.61
Capitalized costs	$ 1.6	$ 0.6	$ 2.7	$ 1.4

Depletion of Oil and Gas Properties Per Physical Unit of Production

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- References

No definition available.

+ Details

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- Definition

The sum of the capitalized costs incurred during the period of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(7)(ii))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

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- Definition

The noncash expense charged against earnings to recognize the consumption of oil and gas reserves that are part of an entities' assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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