Summarized Financial Data - Chevron U.S.A. Inc. (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	$ 244,371	[1]	$ 198,198	[1]	$ 167,402	[1]
Total costs and other deductions	206,072		172,873		153,108
Net income	26,895		19,024		10,483
Chevron U.S.A. Inc. [Member]
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	187,917		145,381		121,553
Total costs and other deductions	178,498		139,984		120,053
Net income	$ 6,899		$ 4,159		$ 1,141

[1] Includes excise, value-added and similar taxes.