Summarized Financial Data - Chevron U.S.A. Inc. (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Subsidiary Statements Captions [Line Items]
Sales and other operating revenues	[1]	$ 129,925	$ 200,494	$ 220,156
Total costs and other deductions		133,635	180,768	192,943
Net income (loss) attributable to CUSA	[2]	4,587	19,241	21,423
Chevron U.S.A. Inc. [Member]
Subsidiary Statements Captions [Line Items]
Sales and other operating revenues		97,766	157,198	174,318
Total costs and other deductions		101,565	153,139	169,984
Net income (loss) attributable to CUSA		$ (1,054)	$ 3,849	$ 3,714

[1] Includes excise, value-added and similar taxes. $7,359; $8,186; $8,492.

[2] There was no effect of dividend equivalents paid on stock units or dilutive impact of employee stock-based awards on earnings.