Quarterly report pursuant to Section 13 or 15(d)

Commodity Derivative Positions (Detail)

v3.19.1
Commodity Derivative Positions (Detail)
$ in Thousands
3 Months Ended
Mar. 31, 2019
USD ($)
bbl
$ / bbl
Settlement Agreement [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 1,721
Crude Oil | Second Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,421
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.48
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 3,361
Crude Oil | Third Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,397
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.50
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 3,430
Crude Oil | Fourth Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,398
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.50
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 3,130
Crude Oil | First Quarter 2020 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.09
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 2,904
Crude Oil | Second Quarter 2020 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.09
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 2,369
Crude Oil | Third Quarter 2020 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.09
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 1,898
Crude Oil | Fourth Quarter 2020 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-WTI
Derivative, Nonmonetary Notional Amount | bbl 6,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 54.09
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 1,518
Louisiana Light Sweet [Member] | Second Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-LLS
Derivative, Nonmonetary Notional Amount | bbl 5,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 59.17
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 3,109
Louisiana Light Sweet [Member] | Third Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-LLS
Derivative, Nonmonetary Notional Amount | bbl 5,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 59.17
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 2,592
Louisiana Light Sweet [Member] | Fourth Quarter 2019 [Member]  
Derivative Instruments Related to Oil and Gas Production [Line Items]  
Derivative, Type of Instrument Swaps-LLS
Derivative, Nonmonetary Notional Amount | bbl 5,000
Derivative, Swap Type, Average Fixed Price | $ / bbl 59.17
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value $ 0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value $ 1,995