v3.8.0.1

Derivative Instruments and Fair Value Measurements - Commodity Derivatives Volumes and Prices (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2017 MMBTU $ / bbl $ / MMBTU bbl
Crude Oil January 2018 – December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 300
Contract Price | 50.00
Crude Oil January 2018 – March 2018 Contract [Member] | Collar [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 1,000
Crude Oil January 2018 – March 2018 Contract [Member] | Collar [Member] | Minimum [Member] |
Derivatives Fair Value [Line Items] |
Contract Price | 50.00
Crude Oil January 2018 – March 2018 Contract [Member] | Collar [Member] | Maximum [Member] |
Derivatives Fair Value [Line Items] |
Contract Price | 55.05
Crude Oil January 2018 – June 2018 Contract [Member] | Collar [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 500
Crude Oil January 2018 – June 2018 Contract [Member] | Collar [Member] | Minimum [Member] |
Derivatives Fair Value [Line Items] |
Contract Price | 55.00
Crude Oil January 2018 – June 2018 Contract [Member] | Collar [Member] | Maximum [Member] |
Derivatives Fair Value [Line Items] |
Contract Price | 60.00
Natural Gas January 2018 - December 2018 Contract One [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | MMBTU | 200,000
Contract Price | $ / MMBTU | 3.085
Natural Gas January 2018 - December 2018 Contract Two [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | MMBTU | 250,000
Contract Price | $ / MMBTU | 3.084
NGLs (C3 - Propane) January 2018 - March 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 450
Contract Price | 30.24
NGLs (IC4 - Isobutane) January 2018 - March 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 50
Contract Price | 36.12
NGLs (NC4 - Butane) January 2018 - March 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 150
Contract Price | 35.70
Crude Oil January 2018 – September 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 700
Contract Price | 60.50
Crude Oil April 2018 – September 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 800
Contract Price | 60.50
NGLs (C2 - Ethane) February 2018 - December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 1,000
Contract Price | 11.424
NGLs (C3 - Propane) February 2018 - December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 600
Contract Price | 32.991
NGLs (IC4 - Isobutane) February 2018 - December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 50
Contract Price | 38.262
NGLs (NC4 - Butane) February 2018 - December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 200
Contract Price | 38.22
NGLs (C5 - Pentane) January 2018 - December 2018 Contract [Member] | Swap [Member] |
Derivatives Fair Value [Line Items] |
Volume Transacted | bbl | 200
Contract Price | 56.364

X
- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountEnergyMeasure
Namespace Prefix: | us-gaap_
Data Type: | num:energyItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal volume used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix: | us-gaap_
Data Type: | num:volumeItemType
Balance Type: | na
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_DerivativesFairValueLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract measured in energy volume but not the derivative contract itself. + References No definition available. + Details
Name: | us-gaap_UnderlyingDerivativeEnergyMeasure
Namespace Prefix: | us-gaap_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | duration

X
- Definition Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract measured in volume but not the derivative contract itself. + References No definition available. + Details
Name: | us-gaap_UnderlyingDerivativeVolume
Namespace Prefix: | us-gaap_
Data Type: | us-types:perUnitItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_CrudeOilJanuaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_SwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_CrudeOilJanuaryTwoThousandEighteenToMarchTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=arex_CollarMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_CrudeOilJanuaryTwoThousandEighteenToJuneTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasJanuaryTwoThousandEighteenToDecemberTwoThousandEighteenContractOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasJanuaryTwoThousandEighteenToDecemberTwoThousandEighteenContractTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC3PropaneJanuaryTwoThousandEighteenToMarchTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsIC4IsobutaneJanuaryTwoThousandEighteenToMarchTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC4ButaneJanuaryTwoThousandEighteenToMarchTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_CrudeOilJanuaryTwoThousandEighteenToSeptemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_CrudeOilAprilTwoThousandEighteenToSeptemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC2EthaneFebruaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC3ProponeFebruaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsIC4IsobutaneFebruaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC4ButaneFebruaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=arex_NaturalGasLiquidsC5PentaneJanuaryTwoThousandEighteenToDecemberTwoThousandEighteenContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |