Investments and Advances - Summary of Investment and Advances and Equity in Earnings (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Investments and Advances	$ 38,402	$ 35,261
Other non-equity method investments	286	285
Total investments and advances	38,688	35,546
Equity in Earnings	3,968	6,327	$ 4,438
United States | Investments and Advances
Schedule of Equity Method Investments [Line Items]
Total investments and advances	7,203	7,500
United States | Equity in Earnings
Schedule of Equity Method Investments [Line Items]
Equity in Earnings	641	1,033	788
International | Investments and Advances
Schedule of Equity Method Investments [Line Items]
Total investments and advances	31,485	28,046
International | Equity in Earnings
Schedule of Equity Method Investments [Line Items]
Equity in Earnings	3,327	5,294	3,650
All Other
Schedule of Equity Method Investments [Line Items]
Investments and Advances	(14)	(16)
Equity in Earnings	0	(2)	(1)
Upstream | Operating Segments
Schedule of Equity Method Investments [Line Items]
Investments and Advances	26,936	23,752
Equity in Earnings	2,787	4,649	3,196
Upstream | Operating Segments | Tengizchevroil
Schedule of Equity Method Investments [Line Items]
Investments and Advances	20,214	16,017
Equity in Earnings	3,067	3,614	2,581
Upstream | Operating Segments | Petropiar
Schedule of Equity Method Investments [Line Items]
Investments and Advances	1,396	1,361
Equity in Earnings	80	317	175
Upstream | Operating Segments | Petroboscan
Schedule of Equity Method Investments [Line Items]
Investments and Advances	1,139	1,315
Equity in Earnings	(11)	357	154
Upstream | Operating Segments | Caspian Pipeline Consortium
Schedule of Equity Method Investments [Line Items]
Investments and Advances	883	1,022
Equity in Earnings	155	170	155
Upstream | Operating Segments | Angola LNG Limited
Schedule of Equity Method Investments [Line Items]
Investments and Advances	2,423	2,496
Equity in Earnings	(26)	172	27
Upstream | Operating Segments | Other
Schedule of Equity Method Investments [Line Items]
Investments and Advances	881	1,541
Equity in Earnings	(478)	19	104
Downstream | Operating Segments
Schedule of Equity Method Investments [Line Items]
Investments and Advances	11,480	11,525
Equity in Earnings	1,181	1,680	1,243
Downstream | Operating Segments | Chevron Phillips Chemical Company LLC
Schedule of Equity Method Investments [Line Items]
Investments and Advances	6,241	6,218
Equity in Earnings	880	1,034	723
Downstream | Operating Segments | GS Caltex Corporation
Schedule of Equity Method Investments [Line Items]
Investments and Advances	3,796	3,924
Equity in Earnings	13	373	290
Downstream | Operating Segments | Other
Schedule of Equity Method Investments [Line Items]
Investments and Advances	1,443	1,383
Equity in Earnings	$ 288	$ 273	$ 230