Property, Plant and Equipment - Narrative (Details)	1 Months Ended		12 Months Ended
	Jul. 31, 2019 USD ($) business	Jun. 30, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	May 31, 2019 MMBoe	Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Impairment of assets			$ 1,206,284,000	$ 0	$ 20,000,000
Total capitalized exploratory well costs			181,616,000	217,326,000	$ 207,855,000		$ 155,103,000
Exploratory well costs capitalized more than one year			181,600,000
MP Gulf of Mexico LLC
Property, Plant and Equipment [Line Items]
Parent ownership interest					80.00%
MP Gulf of Mexico LLC | Petrobas America Inc
Property, Plant and Equipment [Line Items]
Noncontrolling ownership interest					20.00%
LLOG Exploration Offshore L.L.C. and LLOG Bluewater Holdings, L.L.C.
Property, Plant and Equipment [Line Items]
Proved reserves | MMBoe						67
Acquisition, cash paid		$ 1,236,165,000
LLOG Exploration Offshore L.L.C. and LLOG Bluewater Holdings, L.L.C. | Sales thresholds 2019 to 2025
Property, Plant and Equipment [Line Items]
Contingent consideration, maximum			200,000,000
LLOG Exploration Offshore L.L.C. and LLOG Bluewater Holdings, L.L.C. | Net crude oil and condensate revenue
Property, Plant and Equipment [Line Items]
Contingent consideration, maximum			50,000,000.0
Petrobas America Inc
Property, Plant and Equipment [Line Items]
Acquisition, cash paid					$ 780,700,000
Accumulated carried interest paid			29,700,000
Petrobas America Inc | Sales thresholds 2019 to 2025
Property, Plant and Equipment [Line Items]
Contingent consideration, maximum					150,000,000.0
Petrobas America Inc | Enhanced oil recovery projects
Property, Plant and Equipment [Line Items]
Contingent consideration, maximum					50,000,000.0
Malaysia
Property, Plant and Equipment [Line Items]
Number of divested businesses (in businesses) | business	2
Disposal group including discontinued operation, consideration	$ 2,000,000,000.0
Gain (loss) on disposition of business				985,400,000
Disposal group including discontinued operation, contingent consideration paid	$ 100,000,000.0
United States - Onshore
Property, Plant and Equipment [Line Items]
Impairment of assets					20,000,000.0
Vietnam
Property, Plant and Equipment [Line Items]
Exploratory well costs capitalized more than one year			89,700,000
U.S.
Property, Plant and Equipment [Line Items]
Impairment of assets			1,152,515,000	$ 0	$ 20,000,000
Exploratory well costs capitalized more than one year			45,900,000
Brunei
Property, Plant and Equipment [Line Items]
Exploratory well costs capitalized more than one year			25,600,000
MEXICO
Property, Plant and Equipment [Line Items]
Exploratory well costs capitalized more than one year			15,500,000
Canada
Property, Plant and Equipment [Line Items]
Exploratory well costs capitalized more than one year			$ 4,800,000