Summarized Financial Data - Chevron U.S.A. Inc. (Details 1) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Balance Sheet - Chevron U.S.A. Inc.
Current assets	$ 56,008	$ 53,234
Current liabilities	32,656	33,600
Total CUSA net equity	131,289	122,181	116,430	105,811
Chevron U.S.A. Inc. [Member]
Balance Sheet - Chevron U.S.A. Inc.
Current assets	20,850	34,490
Other assets	48,744	47,556
Current liabilities	19,326	19,088
Other liabilities	26,655	26,153
Total CUSA net equity	23,613	36,805
Memo: Total debt	$ 14,641	$ 14,763