Summarized Financial Data - Chevron U.S.A. Inc. (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	[1]	$ 32,767	$ 51,822	$ 101,911	$ 158,383
Costs and other deductions		31,531	45,816	102,178	140,064
Net income attributable to CUSA		$ 2,037	$ 5,593	5,175	15,770
Chevron U.S.A. Inc. [Member]
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues				77,434	124,957
Costs and other deductions				78,116	120,977
Net income attributable to CUSA				$ 424	$ 3,697

[1] * Includes excise, value-added and similar taxes:$1,800 $2,116 $5,642 $6,182