|**Commitments and Contingencies Commitments and Contigencies (Tables)** | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
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|**Commitments and Contingencies Disclosure [Abstract]**                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Supply Commitment                                                       | :For the Twelve Months Ending September 30,Area20192020202120222023 andThroughExpirationTotalExpirationDateNatural gas (MMcf)Wattenberg Field19,14230,85031,02531,02598,717210,759April 30, 2026Delaware Basin48,38741,42625,0755,326—120,214December 31, 2021Gas Marketing7,1177,1367,1176,228—27,598August 31, 2022Total74,64679,41263,21742,57998,717358,571Crude oil (MBbls)Wattenberg Field7,8887,3025,4755,4753,18029,320April 30, 2023Delaware Basin6,6518,8338,2148,03010,05441,782December 31, 2023Total14,53916,13513,68913,50513,23471,102Dollar commitment (in thousands)$92,736$87,056$72,476$71,457$138,271$461,996
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|Area                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|Natural gas (MMcf)                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Wattenberg Field                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Delaware Basin                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Gas Marketing                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Total                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|Crude oil (MBbls)                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Wattenberg Field                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Delaware Basin                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Total                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|Dollar commitment (in thousands)                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  

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