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Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions | Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019
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Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Net derivative liability adjustment | $ 4.3 |  |
Net derivative asset adjustment |  |  | $ 0.5
Commodity forward prices | Discounted Cash Flow |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Estimated future cash flows, measurement input (percent) |  | 2.50% |
Inflation factor | Discounted Cash Flow |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Estimated future cash flows, measurement input (percent) |  | 2.50% |
Market-based Weighted Average Cost of Capital | Discounted Cash Flow | Proved Oil and Gas Properties |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Estimated future cash flows, measurement input (percent) |  | 12.70% |
Market-based Weighted Average Cost of Capital | Discounted Cash Flow | Midstream Assets |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Estimated future cash flows, measurement input (percent) |  | 10.40% |

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- Definition Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties. + References No definition available. + Details
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- Definition Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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