Summarized Financial Data – Chevron Phillips Chemical Company LLC (Details 1) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Subsidiary Statements Captions [Line Items]
Current assets	$ 28,560	$ 29,619
Current liabilities	27,737	31,785
Total CTC net deficit	149,319	146,722	$ 153,886
Chevron Phillips Chemical Company LLC
Subsidiary Statements Captions [Line Items]
Current assets	2,944	2,695
Other assets	13,823	12,770
Current liabilities	1,439	1,418
Other liabilities	2,932	2,569
Total CTC net deficit	$ 12,396	$ 11,478