Properties and Equipment Exploration, geologic, and geophysical expense (Details)	9 Months Ended
Sep. 30, 2020 Wells
Property, Plant and Equipment [Line Items]
Oil and Gas, Exploratory Well Drilled, Net Productive, Number	2
Oil and Gas, Exploratory Well Drilled, Net Nonproductive, Number	0

Number of exploratory oil and gas wells incapable of producing either oil or gas in sufficient quantity to justify completion as oil or gas well.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1205
-Paragraph (a)
-Subparagraph (1)

Name:	srt_ExploratoryWellsDrilledNetNonproductive
Namespace Prefix:	srt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration