Operating Segments and Geographic Data - Segment Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ 49,574	$ 47,216	$ 96,154	$ 96,058
Oil and Gas
Segment Reporting Information [Line Items]
Sales and other operating revenues	49,574	47,216	96,154	96,058
Oil and Gas | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	63,774	58,408	124,176	117,831
Oil and Gas | All Other
Segment Reporting Information [Line Items]
Sales and other operating revenues	153	156	274	265
Oil and Gas | Total All Other
Segment Reporting Information [Line Items]
Sales and other operating revenues	33	36	60	66
Oil and Gas | United States | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	32,922	29,166	64,449	58,287
Oil and Gas | United States | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(120)	(119)	(213)	(198)
Oil and Gas | United States | All Other
Segment Reporting Information [Line Items]
Sales and other operating revenues	153	156	273	264
Oil and Gas | United States | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(10,596)	(8,272)	(20,985)	(15,818)
Oil and Gas | International | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	30,852	29,242	59,727	59,544
Oil and Gas | International | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	0	(1)	(1)	(1)
Oil and Gas | International | All Other
Segment Reporting Information [Line Items]
Sales and other operating revenues	0	0	1	1
Oil and Gas | International | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(3,604)	(2,920)	(7,037)	(5,955)
Oil and Gas | Upstream
Segment Reporting Information [Line Items]
Sales and other operating revenues	10,546	10,145	21,982	22,456
Oil and Gas | Upstream | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	21,508	18,631	43,458	39,450
Oil and Gas | Upstream | United States | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	11,287	8,755	22,454	18,378
Oil and Gas | Upstream | United States | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(7,890)	(6,067)	(15,479)	(11,969)
Oil and Gas | Upstream | International | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	10,221	9,876	21,004	21,072
Oil and Gas | Upstream | International | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(3,072)	(2,419)	(5,997)	(5,025)
Oil and Gas | Downstream
Segment Reporting Information [Line Items]
Sales and other operating revenues	38,995	37,035	74,112	73,536
Oil and Gas | Downstream | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	42,113	39,621	80,444	78,116
Oil and Gas | Downstream | United States | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	21,482	20,255	41,722	39,645
Oil and Gas | Downstream | United States | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	(2,586)	(2,086)	(5,293)	(3,651)
Oil and Gas | Downstream | International | Operating Segments
Segment Reporting Information [Line Items]
Sales and other operating revenues	20,631	19,366	38,722	38,471
Oil and Gas | Downstream | International | Intersegment Eliminations
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ (532)	$ (500)	$ (1,039)	$ (929)