Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments (Details)

v2.4.1.9
Derivative Instruments (Details)
Mar. 31, 2015
Year ending December 31, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 390,000invest_DerivativeNonmonetaryNotionalAmount
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2015Member
Year ending December 31, 2015 | Basis Differential Positions [Member]  
Derivative Instruments  
Weighted average index price (0.35)us-gaap_DerivativeSwapTypeAverageFixedPrice
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2015Member
/ us-gaap_PositionAxis
= ar_BasisDifferentialPositionsMember
Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 290,000invest_DerivativeNonmonetaryNotionalAmount
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
Year ending December 31, 2016 | Basis Differential Positions [Member]  
Derivative Instruments  
Weighted average index price (0.42)us-gaap_DerivativeSwapTypeAverageFixedPrice
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ us-gaap_PositionAxis
= ar_BasisDifferentialPositionsMember
Year ending December 31, 2017  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 125,000invest_DerivativeNonmonetaryNotionalAmount
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
Year ending December 31, 2017 | Basis Differential Positions [Member]  
Derivative Instruments  
Weighted average index price (0.49)us-gaap_DerivativeSwapTypeAverageFixedPrice
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ us-gaap_PositionAxis
= ar_BasisDifferentialPositionsMember
Swaps | Natural gas | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,160,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,160,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,160,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,252,500invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Year ending December 31, 2017  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 900,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | TCO | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 120,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.86us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | TCO | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 120,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.93us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | TCO | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 120,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 5.14us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | TCO | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 60,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.91us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_CGTAPMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Dominion South | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 230,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 5.41us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Dominion South | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 230,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 5.48us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Dominion South | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 230,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 5.74us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | Dominion South | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 272,500invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 5.35us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_DominionSouthMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 770,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.75us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 770,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.79us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 770,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.92us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 750,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.66us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Year ending December 31, 2017  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 410,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.11us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Year ending December 31, 2018  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,192,500invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2018Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.40us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2018Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Year ending December 31, 2019  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 1,347,500invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2019Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.12us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2019Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | NYMEX | Year ending December 31, 2020  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 850,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_YearEndingDecember312020Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.85us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_YearEndingDecember312020Member
/ ar_IndicesAxis
= ar_NYMEXMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CGTLA | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 40,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.86us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CGTLA | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 40,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 3.93us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CGTLA | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 40,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.09us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CGTLA | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 170,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.09us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2016Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CGTLA | Year ending December 31, 2017  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 420,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.27us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_CGTLAMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Natural gas | CCG | Year ending December 31, 2017  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 70,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_CCGMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Weighted average index price 4.57us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_TermCalendar2017Member
/ ar_IndicesAxis
= ar_CCGMember
/ us-gaap_ProductOrServiceAxis
= ar_NaturalGasMember
Swaps | Oil | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Oil | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Oil | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Oil | NYMEX-WTI | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Weighted average index price 64.21us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Oil | NYMEX-WTI | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Weighted average index price 64.84us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Oil | NYMEX-WTI | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 3,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Weighted average index price 65.67us-gaap_DerivativeSwapTypeAverageFixedPrice
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingDecember312015Member
/ ar_IndicesAxis
= ar_NYMEXWTIMember
/ us-gaap_ProductOrServiceAxis
= us-gaap_CrudeOilMember
Swaps | Propane | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingJune302015Member
/ us-gaap_ProductOrServiceAxis
= us-gaap_PublicUtilitiesInventoryPropaneMember
Swaps | Propane | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember
/ ar_DerivativeContractTermAxis
= ar_ThreeMonthsEndingSeptember302015Member
/ us-gaap_ProductOrServiceAxis
= us-gaap_PublicUtilitiesInventoryPropaneMember
Swaps | Propane | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
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Swaps | Propane | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 27,000invest_DerivativeNonmonetaryNotionalAmount
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Swaps | Propane | Mont Belvieu-TET | Three months ending June 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
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Weighted average index price 0.60us-gaap_DerivativeSwapTypeAverageFixedPrice
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Swaps | Propane | Mont Belvieu-TET | Three months ending September 30, 2015  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
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Weighted average index price 0.62us-gaap_DerivativeSwapTypeAverageFixedPrice
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Swaps | Propane | Mont Belvieu-TET | Three months ending December 31, 2015 [Member]  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 23,000invest_DerivativeNonmonetaryNotionalAmount
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Weighted average index price 0.64us-gaap_DerivativeSwapTypeAverageFixedPrice
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Swaps | Propane | Mont Belvieu-TET | Year ending December 31, 2016  
Derivative Instruments  
Notional amount (MMBtu/Bbls per day) 27,000invest_DerivativeNonmonetaryNotionalAmount
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Weighted average index price 0.58us-gaap_DerivativeSwapTypeAverageFixedPrice
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