Derivative Financial Instruments (Details) - Jun. 30, 2015 $ in Thousands	USD ($) bbl / mo MMBTU / mo $ / MMBTU $ / BBL
Summary of contracts for oil and natural gas
Fair Value of Asset (Liability)	$ 23,460
Open costless collar contracts | Oil
Summary of contracts for oil and natural gas
Fair Value of Asset (Liability)	$ 18,636
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 80 Price Floor, 100.00 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	80.00
Price Ceiling | $ / BBL	100
Fair Value of Asset (Liability)	$ 2,376
Open costless collar contracts | Oil | Open Oil Collar Contract, 50,000 Notional Amount, 50 Price Floor, 67.85 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	50,000
Price Floor | $ / BBL	50
Price Ceiling | $ / BBL	67.85
Fair Value of Asset (Liability)	$ (110)
Open costless collar contracts | Oil | Open Oil Collar Contract, 50,000 Notional Amount, 45 Price Floor, 77.75 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	07/01/2016 - 12/31/2016
Notional Quantity | bbl / mo	50,000
Price Floor | $ / BBL	45
Price Ceiling | $ / BBL	77.75
Fair Value of Asset (Liability)	$ (77)
Open costless collar contracts | Oil | Open Oil Collar Contract, 40,000 Notional Amount, 45 Price Floor, 68.75 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	40,000
Price Floor | $ / BBL	45
Price Ceiling | $ / BBL	68.75
Fair Value of Asset (Liability)	$ (161)
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 80 Price Floor, 101.00 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	80.00
Price Ceiling | $ / BBL	101
Fair Value of Asset (Liability)	$ 2,377
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 83 Price Floor, 96.12 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	83.00
Price Ceiling | $ / BBL	96.12
Fair Value of Asset (Liability)	$ 2,726
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 83 Price Floor, 97.00 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	83.00
Price Ceiling | $ / BBL	97.00
Fair Value of Asset (Liability)	$ 2,725
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 85 Price Floor, 99.00 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	85
Price Ceiling | $ / BBL	99
Fair Value of Asset (Liability)	$ 2,963
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 85 Price Floor, 100.00 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	85
Price Ceiling | $ / BBL	100
Fair Value of Asset (Liability)	$ 2,963
Open costless collar contracts | Oil | Open Oil Collar Contract, 20,000 Notional Amount, 85 Price Floor, 105.10 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | bbl / mo	20,000
Price Floor | $ / BBL	85
Price Ceiling | $ / BBL	105.10
Fair Value of Asset (Liability)	$ 2,964
Open costless collar contracts | Oil | Open Oil Collar Contract, 40,000 Notional Amount, 55 Price Floor, 68.35 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2016
Notional Quantity | bbl / mo	40,000
Price Floor | $ / BBL	55.00
Price Ceiling | $ / BBL	68.35
Fair Value of Asset (Liability)	$ 156
Open costless collar contracts | Oil | Open Oil Collar Contract, 40,000 Notional Amount, 43 Price Floor, 77.05 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	01/01/2016 - 12/31/2016
Notional Quantity | bbl / mo	40,000
Price Floor | $ / BBL	43
Price Ceiling | $ / BBL	77.05
Fair Value of Asset (Liability)	$ (266)
Open costless collar contracts | Natural Gas
Summary of contracts for oil and natural gas
Fair Value of Asset (Liability)	$ 3,797
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 150,000 Notional Amount, 2.75 Price Floor, 3.19 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 10/31/2015
Notional Quantity | MMBTU / mo	150,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.19
Fair Value of Asset (Liability)	$ 29
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 2.75 Price Floor, 3.05 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.05
Fair Value of Asset (Liability)	$ (19)
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 2.75 Price Floor, 3.15 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.15
Fair Value of Asset (Liability)	$ (2)
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 2.75 Price Floor, 3.11 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.11
Fair Value of Asset (Liability)	$ (8)
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 300,000 Notional Amount, 2.88 Price Floor, 3.18 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	300,000
Price Floor | $ / MMBTU	2.88
Price Ceiling | $ / MMBTU	3.18
Fair Value of Asset (Liability)	$ 128
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 3.75 Price Floor, 4.36 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	4.36
Fair Value of Asset (Liability)	$ 523
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 3.75Price Floor, 4.45 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	4.45
Fair Value of Asset (Liability)	$ 524
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 3.75 Price Floor, 4.60 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	4.60
Fair Value of Asset (Liability)	$ 526
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 3.75 Price Floor, 4.65 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	4.65
Fair Value of Asset (Liability)	$ 518
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 200,000 Notional Amount, 3.75 Price Floor, 5.04 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	200,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	5.04
Fair Value of Asset (Liability)	$ 1,057
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 100,000 Notional Amount, 3.75 Price Floor, 5.34 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	07/01/2015 - 12/31/2015
Notional Quantity | MMBTU / mo	100,000
Price Floor | $ / MMBTU	3.75
Price Ceiling | $ / MMBTU	5.34
Fair Value of Asset (Liability)	$ 529
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 200,000 Notional Amount, 2.75 Price Floor, 3.50 Price Ceiling
Summary of contracts for oil and natural gas
Calculation Period	01/01/2016 - 12/31/2016
Notional Quantity | MMBTU / mo	200,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.50
Fair Value of Asset (Liability)	$ (164)
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 200,000 Notional Amount, 2.75 Price Floor, 3.50 Price Ceiling [Member] [Member]
Summary of contracts for oil and natural gas
Calculation Period	01/01/2016 - 12/31/2016
Notional Quantity | MMBTU / mo	200,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.86
Fair Value of Asset (Liability)	$ 38
Open costless collar contracts | Natural Gas | Open Natural Gas Collar Contract, 300,000 Notional Amount, 2.75 Price Floor, 3.95 Price Ceiling [Member]
Summary of contracts for oil and natural gas
Calculation Period	01/01/2016 - 12/31/2016
Notional Quantity | MMBTU / mo	300,000
Price Floor | $ / MMBTU	2.75
Price Ceiling | $ / MMBTU	3.95
Fair Value of Asset (Liability)	$ 118