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Number of Productive Crude Oil and Natural Gas Wells in which we Held an Interest (Parenthetical) (Detail) | Jun. 30, 2018 Wells
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Productive wells [Line Items] |
Crude oil wells, Gross | 1,411
Crude oil wells, Net | 747
Natural gas wells, Gross | 6,831
Natural gas wells, Net | 2,068
United States [member] |
Productive wells [Line Items] |
Crude oil wells, Gross | 998
Crude oil wells, Net | 547
Natural gas wells, Gross | 6,660
Natural gas wells, Net | 2,012
United States [member] | Discontinued Operations - Onshore US Cash Generating Units [Member] |
Productive wells [Line Items] |
Crude oil wells, Gross | 971
Crude oil wells, Net | 536
Natural gas wells, Gross | 6,660
Natural gas wells, Net | 2,012

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- Definition The total number of producing gas wells and gas wells capable of production, in which the entity owns an undivided working interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1208 -Paragraph (a) + Details
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- Definition The total number of producing gas wells and gas wells capable of production, in which the entity owns a fractional working interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1208 -Paragraph (a) + Details
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- Definition The total number of producing oil wells and oil wells capable of production, in which the entity owns an undivided working interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1208 -Paragraph (a) + Details
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- Definition The total number of producing oil wells and oil wells capable of production, in which the entity owns a fractional working interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1208 -Paragraph (a) + Details
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