Supplemental Gas Data (unaudited) Future Cash Flow of Proved Reserves (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) usd_per_mcf usd_per_bbl	Dec. 31, 2018 USD ($) usd_per_mcf usd_per_bbl	Dec. 31, 2017 USD ($) usd_per_mcf usd_per_bbl	Dec. 31, 2016 USD ($)
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Revenues	$ 19,489,588	$ 26,610,100	$ 19,261,578
Production Costs	(7,903,120)	(7,730,451)	(7,234,303)
Development Costs	(1,121,073)	(1,600,128)	(1,710,585)
Income Tax Expense	(2,720,994)	(4,147,075)	(2,475,981)
Future Net Cash Flows	7,744,401	13,132,446	7,840,709
Discounted to Present Value at a 10% Annual Rate	(4,673,932)	(8,476,989)	(4,709,311)
Total Standardized Measure of Discounted Net Cash Flows	$ 3,070,469	$ 4,655,457	$ 3,131,398	$ 955,117
Natural Gas
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Adjusted oil price (in usd per barrel) \| usd_per_mcf	2.24	3.28	2.44
Oil
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Adjusted oil price (in usd per barrel) \| usd_per_bbl	44.31	51.68	38.65
NGLs
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Adjusted oil price (in usd per barrel) \| usd_per_bbl	19.10	27.58	23.61

Future Net Cash Flows Relating to Proved Oil and Gas Reserves, Adjusted Price

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Amount of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for costs to be incurred in developing proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for income tax, based on the future income less future expense derived from production and sale of proved oil and gas reserves.

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Amount, after future accumulated cash outflow for development and production costs and future income tax, of estimated future accumulated cash inflow from the sale of proved oil and gas reserves.

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Amount of estimated future accumulated cash outflow for costs to be incurred in producing proved oil and gas reserves.

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Amount of discount on future accumulated cash inflow, after deducting future accumulated cash outflow for development and production costs and future income tax, from sale of proved oil and gas reserves, using a discount rate of ten percent a year.

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Amount of discounted future accumulated cash inflow relating to proved oil and gas reserves.

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