Summarized Financial Data - Chevron U.S.A. Inc. (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	[1]	$ 31,524	$ 23,070
Costs and other deductions		30,292	25,264
Net income (loss) attributable to CUSA		2,682	(725)
Chevron U.S.A. Inc. [Member]
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues		24,408	16,864
Costs and other deductions		24,099	17,996
Net income (loss) attributable to CUSA		$ 421	$ (444)

[1] Includes excise, value-added and similar taxes: $1,677, $1,652