Summarized Financial Data - Chevron U.S.A. Inc. (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	$ 58,896	$ 58,412
Total costs and other deductions	48,636	49,219
Net income	6,471	6,211
Chevron U.S.A. Inc. [Member]
Statement of Income - Chevron U.S.A. Inc.
Sales and other operating revenues	47,134	44,261
Total costs and other deductions	45,106	42,338
Net income	$ 1,364	$ 1,427