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v3.19.1

SUBSEQUENT EVENTS (Details) shares in Millions |  | 1 Months Ended | 3 Months Ended |  |
--- | --- | --- | --- | --- | ---
Apr. 26, 2019 USD ($) shares | Apr. 30, 2019 USD ($) $ / bbl shares bbl | Mar. 31, 2019 USD ($) $ / MMBTU | Mar. 31, 2018 USD ($) | Jan. 31, 2019 USD ($) | Jan. 31, 2018 USD ($)
Subsequent Event [Line Items] |  |  |  |  |  |
Amount of shares repurchased |  |  | $ 28,330,000 | $ 99,997,000 |  |
Stock repurchase program, amount authorized to acquire |  |  |  |  | $ 400,000,000.0 | $ 100,000,000
Fixed Price Swap 2019 |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Weighted average price (in usd per Bbl) | $ / MMBTU |  |  | 3.05 |  |  |
Subsequent Event |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Shares repurchased (in shares) | shares | 3.8 | 0.2 |  |  |  |
Amount of shares repurchased | $ 30,000,000 | $ 1,800,000 |  |  |  |
Stock repurchase program, amount authorized to acquire | $ 370,000,013 |  |  |  |  |
Subsequent Event | Fixed Price Swap 2019 | Oil derivatives |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Daily Volume (Bbls/day) | bbl |  | 3,000 |  |  |  |
Weighted average price (in usd per Bbl) | $ / bbl |  | 61.55 |  |  |  |
Subsequent Event | Fixed Price Swap 2019 | C5 Pentane |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Daily Volume (Bbls/day) | bbl |  | 500 |  |  |  |
Weighted average price (in usd per Bbl) | $ / bbl |  | 53.34 |  |  |  |
Subsequent Event | Fixed Price Swap 2020 |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Daily Volume (Bbls/day) | bbl |  | 6,000 |  |  |  |
Weighted average price (in usd per Bbl) | $ / bbl |  | 59.82 |  |  |  |

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