Operating Segments and Geographic Data - Earnings by Major Operating Area (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	$ (207)	$ 2,580	$ (4,878)	$ 9,534
Operating Segments
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	527	3,532	(2,549)	11,119
Operating Segments | Upstream
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	235	2,704	(2,934)	9,310
Operating Segments | Upstream | United States
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	116	727	(1,709)	2,371
Operating Segments | Upstream | International
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	119	1,977	(1,225)	6,939
Operating Segments | Downstream
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	292	828	385	1,809
Operating Segments | Downstream | United States
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	141	389	(397)	1,071
Operating Segments | Downstream | International
Segment Reporting Information [Line Items]
Net Income (Loss) Attributable to Chevron Corporation	151	439	782	738
All Other
Segment Reporting Information [Line Items]
Interest expense	(153)	(187)	(471)	(591)
Interest income	7	48	43	142
Other	$ (588)	$ (813)	$ (1,901)	$ (1,136)