XML 83 R71.htm IDEA: XBRL DOCUMENT
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Subsequent Events (Details) |  |  | 1 Months Ended | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 26, 2018 USD ($) | Mar. 31, 2018 MMBTU $ / bbl $ / MMBTU bbl | Apr. 30, 2018 MMBTU $ / bbl $ / MMBTU bbl | Mar. 31, 2018 USD ($) $ / bbl $ / MMBTU | Mar. 31, 2017 USD ($) | May 31, 2018 USD ($) | Jan. 31, 2018 USD ($) | Dec. 31, 2017
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Payments for equity method investments | $ |  |  |  | $ 1,569,000 | $ 10,673,000 |  |  |
Stock repurchase program, amount authorized to acquire | $ |  |  |  |  |  |  | $ 100,000,000 |
Strike Force Midstream LLC |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Equity method investment, ownership interest, percent |  | 25.00% |  | 25.00% |  |  |  | 25.00%
Payments for equity method investments | $ |  |  |  |  | $ 10,000,000 |  |  |
NYMEX Henry Hub Swap - 2018 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  | 927,000 |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  | 3.02 |  | 3.02 |  |  |  |
NYMEX Henry Hub Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  | 647,000 |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  | 2.84 |  | 2.84 |  |  |  |
NYMEX WTI Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl |  | 57.62 |  | 57.62 |  |  |  |
Daily volume (in Bbls) | bbl |  | 3,000 |  |  |  |  |  |
Mont Belvieu C3 Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl |  | 27.05 |  | 27.05 |  |  |  |
Daily volume (in Bbls) | bbl |  | 1,000 |  |  |  |  |  |
NYMEX Henry Hub Swap - 2020 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  | 45,000 |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  | 2.77 |  | 2.77 |  |  |  |
Subsequent event | Strike Force Midstream LLC |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Payments for equity method investments | $ | $ 175,000,000 |  |  |  |  |  |  |
Subsequent event | NYMEX Henry Hub Swap - 2018 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  |  | 53,000 |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  |  | 2.84 |  |  |  |  |
Subsequent event | NYMEX Henry Hub Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  |  | 15,000 |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  |  | 2.76 |  |  |  |  |
Subsequent event | NYMEX WTI Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl |  |  | 60.24 |  |  |  |  |
Daily volume (in Bbls) | bbl |  |  | 1,000 |  |  |  |  |
Subsequent event | Mont Belvieu C3 Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl |  |  | 28.04 |  |  |  |  |
Daily volume (in Bbls) | bbl |  |  | 2,000 |  |  |  |  |
Subsequent event | Mont Belvieu C5 Swap - 2019 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl |  |  | 54.08 |  |  |  |  |
Daily volume (in Bbls) | bbl |  |  | 500 |  |  |  |  |
Subsequent event | NYMEX Henry Hub Swap - 2020 |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Daily volume (in MMBtu) | MMBTU |  |  | 5,000 |  |  |  |  |
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU |  |  | 2.76 |  |  |  |  |
Minimum | Subsequent event |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Stock repurchase program, amount authorized to acquire | $ |  |  |  |  |  | $ 100,000,000 |  |
Maximum | Subsequent event |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Stock repurchase program, amount authorized to acquire | $ |  |  |  |  |  | $ 200,000,000 |  |

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