Oil and Natural Gas Property Transactions - Narrative (Details) shares in Millions, $ / Mcf in Millions, $ in Millions		11 Months Ended	12 Months Ended
	Feb. 01, 2019 USD ($) shares	Dec. 31, 2019 USD ($) a well	Dec. 31, 2019 USD ($) a well day $ / BTU $ / bbl	Dec. 31, 2018 USD ($) a well day $ / BTU	Dec. 31, 2017 USD ($) a well $ / Mcf
Business Acquisition [Line Items]
Revenues			$ 8,595	$ 10,030	$ 10,039
Proceeds from divestitures of proved and unproved properties			130	2,231	1,249
Gain (loss) on sale of oil and natural gas properties			$ 0	0
Consecutive trading days | day			5
Natural gas
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / BTU			2.82
Mid-Continent
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties				491
Gain (loss) on sale of oil and natural gas properties				$ 12
Area of land, net (in acres) | a				238,500
Productive gas wells, number of wells, net | well				3,200
Other properties
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties				$ 37	350
Haynesville shale
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties					915
Gain (loss) on sale of oil and natural gas properties					$ 326
Area of land, net (in acres) | a					119,500
Productive gas wells, number of wells, net | well					576
Haynesville shale | Natural gas
Business Acquisition [Line Items]
Proved developed reserves (volume) | $ / Mcf					80
Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Proceeds from divestitures of proved and unproved properties			$ 130
Gain (loss) on sale of oil and natural gas properties			$ 46
Utica shale | Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Area of land, gross (in acres) | a		1,500,000	1,500,000
Area of land, net (in acres) | a		900,000	900,000
Productive gas wells, number of wells, net | well		920	920
Consideration received		$ 1,868	$ 1,868
Utica shale | Disposal group, disposed of by sale, not discontinued operations | Synthetic gas
Business Acquisition [Line Items]
Net rentable area (in acres) | a		320,000	320,000
Future natural gas prices 2023 | Natural gas
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / BTU			3.00
Future natural gas prices | Utica shale | Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Consideration received				$ 100
Period of trading days | day				20
Consecutive trading days | day				30
2022 NYMEX natural gas | Future natural gas prices 2023 | Utica shale | Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / BTU				3.25
2022 NYMEX natural gas | Future natural gas prices | Utica shale | Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Gain (loss) on sale of oil and natural gas properties			$ (273)
Consideration received				$ 50
2022 NYMEX natural gas | Future natural gas prices 2022 | Utica shale | Disposal group, disposed of by sale, not discontinued operations
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / BTU				3.00
Wildhorse resource development corporation
Business Acquisition [Line Items]
Common stock issued in the merger (in shares) | shares	717.4
Cash	$ 381
Revenues		$ 752
Operating expenses		810
Other expenses		$ 83
Energy related derivative | Oil
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / bbl			56.33
Energy related derivative | Future NYMEX oil prices 2023 | Oil
Business Acquisition [Line Items]
Average sales price (in usd per unit) | $ / bbl			61.17