Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue
Total revenues from contracts with customers	$ 715,201	$ 1,271,613
Gain (loss) on derivatives not designated as hedges	389,436	(131,996)
Total operating revenues	1,107,057	1,143,173
Natural gas sales
Disaggregation of Revenue
Total revenues from contracts with customers	673,230	1,193,849
NGLs sales
Disaggregation of Revenue
Total revenues from contracts with customers	35,756	69,604
Oil sales
Disaggregation of Revenue
Total revenues from contracts with customers	6,215	8,160
Net marketing services and other
Disaggregation of Revenue
Net marketing services and other	$ 2,420	$ 3,556

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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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 that is not accounted for under Topic 606, classified as other.

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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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