Investments and Advances (Details 1) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Chevron
Schedule of Investments [Line Items]
Total revenues	$ 33,460	$ 27,787	$ 33,492
Income before income tax expense	5,712	3,670	6,279
Net income attributable to affiliates	4,468	2,876	4,691
Current assets	13,568	13,743	10,657
Noncurrent assets	32,643	28,854	26,607
Current liabilities	10,201	8,996	7,351
Noncurrent liabilities	4,224	4,255	3,909
Total net equity	31,786	29,346	26,004
Affiliates
Schedule of Investments [Line Items]
Total revenues	70,744	59,253	71,389
Income before income tax expense	13,487	6,587	13,129
Net income attributable to affiliates	10,751	5,127	10,649
Current assets	33,883	33,406	27,162
Noncurrent assets	82,261	75,258	71,650
Current liabilities	26,873	24,793	20,559
Noncurrent liabilities	21,447	22,671	18,560
Total net equity	$ 67,824	$ 61,200	$ 59,693