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Subsequent Events - Narrative (Details) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 28, 2018 $ / bbl bbl | Jan. 31, 2018 USD ($) MMBTU $ / bbl $ / MMBTU bbl | Dec. 31, 2017 MMBTU $ / MMBTU
Subsequent event |  |  |
Derivative [Line Items] |  |  |
Stock repurchase program, authorized amount | $ |  | $ 100,000,000.0 |
Fixed Price Swap 2018 | Subsequent event | NYMEX WTI |  |  |
Derivative [Line Items] |  |  |
Daily volume (Bbls/day) | bbl |  | 1,000 |
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl |  | 62.18 |
Fixed Price Swap 2018 | Subsequent event | Mont Belvieu Propane 2019 Fixed Price Swap |  |  |
Derivative [Line Items] |  |  |
Daily volume (Bbls/day) | bbl | 500 |  |
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl | 35.54 |  |
Fixed Price Swap 2019 |  |  |
Derivative [Line Items] |  |  |
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU |  |  | 3.05
Daily volume (MMBtu/day) | MMBTU |  |  | 100,000
Fixed Price Swap 2019 | Subsequent event | NYMEX WTI |  |  |
Derivative [Line Items] |  |  |
Daily volume (Bbls/day) | bbl | 2,000 |  |
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / bbl | 57.75 |  |
Fixed Price Swap 2019 | Subsequent event | NYMEX Natural Gas 2018 Fixed Price Swap |  |  |
Derivative [Line Items] |  |  |
Weighted average price of derivative swap (usd per MMBtu or Bbls) | $ / MMBTU |  | 2.79 |
Daily volume (MMBtu/day) | MMBTU |  | 242,000 |

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