Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues and other	$ 128,036	$ 141,778
Gains (losses) on oil derivatives	199,194	(63,124)
Total revenues and other	339,265	76,539
Oil sales
Disaggregation of Revenue [Line Items]
Revenues and other	118,310	123,450
Natural gas sales
Disaggregation of Revenue [Line Items]
Revenues and other	3,368	6,715
Gains (losses) on oil derivatives	(12,035)	2,115
Natural gas liquids sales
Disaggregation of Revenue [Line Items]
Revenues and other	420	937
Electricity sales
Disaggregation of Revenue [Line Items]
Revenues and other	5,461	9,729
Marketing revenues
Disaggregation of Revenue [Line Items]
Revenues and other	453	830
Other revenues
Disaggregation of Revenue [Line Items]
Revenues and other	24	117
Oil
Disaggregation of Revenue [Line Items]
Gains (losses) on oil derivatives	$ 211,229	$ (65,239)

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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