Derivative Instruments and Hedging Activities - Derivative Instruments Summary (Details)	Dec. 31, 2018 bbl / d MMBTU / d $ / bbl $ / MMBTU
Crude Oil | 2019 Swaps NYMEX WTI
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	22,000
Weighted Average Fixed Price (in usd per unit)	56.96
Crude Oil | 2019 Three-Way Collars NYMEX WTI
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	33,000
Weighted Average Short Put Price (in usd per unit)	49.35
Weighted Average Floor Price (in usd per unit)	59.35
Weighted Average Ceiling Price (in usd per unit)	72.25
Crude Oil | 2019 Swaps ICE Brent
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	5,000
Weighted Average Fixed Price (in usd per unit)	57.00
Crude Oil | 2019 Three-Way Collars ICE Brent
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	3,000
Weighted Average Short Put Price (in usd per unit)	43.00
Weighted Average Floor Price (in usd per unit)	50.00
Weighted Average Ceiling Price (in usd per unit)	64.07
Crude Oil | 2019 Basis Swaps
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	27,000
Weighted Average Differential (in usd per unit)	(3.23)
Crude Oil | 2020 Swaption NYMEX WTI
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	5,000
Weighted Average Fixed Price (in usd per unit)	61.79
Crude Oil | 2020 Basis Swap
Derivative [Line Items]
Volume Per Day (in units per day) | bbl / d	15,000
Weighted Average Differential (in usd per unit)	(5.01)
Natural Gas | 2019 Swaps NYMEX HH
Derivative [Line Items]
Volume Per Day (in units per day) | MMBTU / d	86,500
Weighted Average Fixed Price (in usd per unit) | $ / MMBTU	4.36
Natural Gas | 2019 Three-Way Collars NYMEX HH
Derivative [Line Items]
Volume Per Day (in units per day) | MMBTU / d	104,000
Weighted Average Short Put Price (in usd per unit) | $ / MMBTU	2.25
Weighted Average Floor Price (in usd per unit) | $ / MMBTU	2.65
Weighted Average Ceiling Price (in usd per unit) | $ / MMBTU	2.95
Natural Gas | 2019 Three-Way Collars NYMEX HH
Derivative [Line Items]
Volume Per Day (in units per day) | MMBTU / d	21,500
Weighted Average Short Put Price (in usd per unit) | $ / MMBTU	3.00
Weighted Average Floor Price (in usd per unit) | $ / MMBTU	3.25
Weighted Average Ceiling Price (in usd per unit) | $ / MMBTU	4.08
Natural Gas | 2019 Basis Swaps
Derivative [Line Items]
Volume Per Day (in units per day) | MMBTU / d	52,000
Weighted Average Differential (in usd per unit) | $ / MMBTU	(0.74)