Summarized Financial Data - Chevron Phillips Chemical Company LLC (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Summarized Financial Data - Chevron Transport Corporation
Sales and other operating revenues	[1]	$ 32,877	$ 27,844	$ 64,401	$ 50,914
Costs and other deductions		32,527	31,352	62,819	56,616
Net income attributable to TCO		$ 1,450	$ (1,470)	$ 4,132	(2,195)
Chevron Phillips Chemical Company LLC
Subsidiary Statements Captions [Line Items]
Equity method investment, ownership percentage		50.00%		50.00%
Percentage of affiliate by summarized financial information		100.00%		100.00%
Summarized Financial Data - Chevron Transport Corporation
Sales and other operating revenues				$ 4,701	4,071
Costs and other deductions				3,787	3,312
Net income attributable to TCO				$ 1,093	$ 988

[1] Includes excise, value-added and similar taxes: $1,771, $1,784, $3,448, $3,436