Revenues, Key product revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of revenue [Abstract]
Sales and other operating revenues	$ 5,546	$ 9,048	$ 13,040	$ 17,826
Olefins & co-products [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	460	745	1,127	1,493
Polyethylene [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	1,277	1,538	2,736	3,204
Polypropylene [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	969	1,317	2,070	2,632
Propylene oxide and derivatives [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	332	489	796	1,017
Oxyfuels and related products [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	389	797	1,096	1,461
Intermediate chemicals [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	404	705	948	1,345
Compounding and solutions [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	549	1,062	1,461	2,202
Advanced polymers [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	151	196	332	394
Refined products [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	855	2,011	2,191	3,754
Other [Member]
Disaggregation of revenue [Abstract]
Sales and other operating revenues	$ 160	$ 188	$ 283	$ 324