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Acquisitions (Details) |  |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Aug. 31, 2015 USD ($) | Jun. 29, 2015 USD ($) a | Jun. 12, 2015 USD ($) a well mi Mcf | Jun. 09, 2015 USD ($) a | Dec. 31, 2015 USD ($) | Apr. 30, 2015 USD ($) a | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Deductions to cash held in escrow |  |  |  |  |  |  | $ (185,000,000) | $ 0 | $ 0
Paloma Partners III, LLC |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price | $ 302,300,000 |  |  |  |  | $ 301,900,000 |  |  |
Net nonproducing oil and gas acreage (in acres) | a |  |  |  |  |  | 24,000 |  |  |
Amount put in escrow | $ 30,100,000 |  |  |  |  | $ 75,000,000 |  |  |
American Energy - Utica, LLC |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  | $ 405,400,000 |  |  |  |  |  |  |
Amount put in escrow |  |  | $ 67,100,000 |  |  |  |  |  |
Cash, net of purchase price adjustments |  | 405,000,000 | 405,029,000 |  |  |  |  |  |
Deductions to cash held in escrow |  |  |  |  | $ 2,400,000 |  |  |  |
Goodwill |  |  | 0 |  |  |  |  |  |
Bargain purchase gain |  |  | 0 |  |  |  |  |  |
Belmont And Jefferson Counties, Ohio | American Energy - Utica, LLC |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  |  |  | $ 68,200,000 |  |  |  |  |
Gross and net acquired oil and gas acreage (in acres) | a |  |  |  | 6,198 |  |  |  |  |
Monroe County, Ohio | American Energy - Utica, LLC |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  | $ 18,200,000 | $ 319,000,000 |  |  |  |  |  |
Net nonproducing oil and gas acreage (in acres) | a |  | 1,900 | 27,228 |  |  |  |  |  |
Gross oil and gas acreage acquired (in acres) | a |  | 4,950 | 38,965 |  |  |  |  |  |
Net average per day production volume (MMcf) | Mcf |  |  | 14,600 |  |  |  |  |  |
Gross number of wells acquired | well |  |  | 18 |  |  |  |  |  |
Net number of wells acquired | well |  |  | 11.3 |  |  |  |  |  |
Length of gas gathering transportation | mi |  |  | 11 |  |  |  |  |  |
Number of well pad locations | well |  |  | 4 |  |  |  |  |  |

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