Asset Acquisitions and Dispositions (Narrative - Acquisition of Concho Resources Inc.) (Details) $ in Millions			3 Months Ended	12 Months Ended
	Feb. 08, 2021 USD ($)	Jan. 15, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Capitalized costs, proved properties				$ 114,274	$ 114,274	$ 94,312
Capitalized costs, unproved properties				10,993	10,993	4,141
Income tax provision					4,633	(485)	$ 2,267
Total Revenues and Other Income					48,349	19,256	36,670
Net Income (Loss) Attributable to ConocoPhillips					8,079	(2,701)	$ 7,189
Concho Resources Incorporated [Member]
Business Acquisition [Line Items]
Exchange ratio		1.46
Total Consideration		$ 13,125
Capitalized costs, proved properties		11,800		20,000	20,000
Capitalized costs, unproved properties		$ 6,900		6,900	$ 6,900
Transaction Cost			$ 157	157
Total Revenues and Other Income				6,571
Net Income (Loss) Attributable to ConocoPhillips				2,330
Concho Resources Incorporated [Member] | Concho Resources Inc. [Member]
Business Acquisition [Line Items]
Income tax provision	$ 75
Impairment of Oil and Gas Properties						10,500
Goodwill, impairment loss						$ 1,900
Concho Resources Incorporated [Member] | Commodity Contract [Member]
Business Acquisition [Line Items]
Loss from commodity derivatives, before tax				305
Loss from commodity derivatives, after tax				$ 233