Operating Segments and Geographic Data - Segment Sales and Operating Revenues (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	$ 155,606	$ 94,471	$ 139,865
Oil and Gas
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	155,606	94,471	139,865
Oil and Gas \| Upstream
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	43,992	26,311	31,707
Oil and Gas \| Downstream
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	111,490	68,083	107,912
Oil and Gas \| Operating Segments
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	185,955	113,665	172,995
Oil and Gas \| Operating Segments \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	86,934	47,910	79,693
Oil and Gas \| Operating Segments \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	99,021	65,755	93,302
Oil and Gas \| Operating Segments \| Upstream
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	70,140	41,381	58,986
Oil and Gas \| Operating Segments \| Upstream \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	29,219	14,577	23,358
Oil and Gas \| Operating Segments \| Upstream \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	40,921	26,804	35,628
Oil and Gas \| Operating Segments \| Downstream
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	115,307	71,525	112,925
Oil and Gas \| Operating Segments \| Downstream \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	57,209	32,589	55,271
Oil and Gas \| Operating Segments \| Downstream \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	58,098	38,936	57,654
Oil and Gas \| Intersegment \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(382)	(667)	(818)
Oil and Gas \| Intersegment \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(2)	(15)	(20)
Oil and Gas \| Intersegment \| Upstream \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(15,154)	(8,068)	(14,944)
Oil and Gas \| Intersegment \| Upstream \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(10,994)	(7,002)	(12,335)
Oil and Gas \| Intersegment \| Downstream \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(2,296)	(2,150)	(3,924)
Oil and Gas \| Intersegment \| Downstream \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(1,521)	(1,292)	(1,089)
Oil and Gas \| Corporate And Eliminations
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	124	77	246
Oil and Gas \| Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	508	759	1,084
Oil and Gas \| Corporate, Non-Segment \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	506	744	1,064
Oil and Gas \| Corporate, Non-Segment \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	2	15	20
Oil and Gas \| Intersegment Elimination \| United States
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	(17,832)	(10,885)	(19,686)
Oil and Gas \| Intersegment Elimination \| International
Segment Reporting Information [Line Items]
Total Sales and Other Operating Revenues	$ (12,517)	$ (8,309)	$ (13,444)