Revenue - Disaggregation of revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of revenue
Revenue from customers	$ 6,880	$ 4,018	$ 18,166	$ 12,576
United States
Disaggregation of revenue
Revenue from customers	5,995	3,346	15,883	10,404
International
Disaggregation of revenue
Revenue from customers	1,146	854	3,041	2,715
Eliminations
Disaggregation of revenue
Revenue from customers	(261)	(182)	(758)	(543)
Oil and gas
Disaggregation of revenue
Revenue from customers	5,056	2,882	13,463	9,016
Oil and gas | Oil
Disaggregation of revenue
Revenue from customers	3,822	2,319	10,546	7,484
Oil and gas | NGL
Disaggregation of revenue
Revenue from customers	732	305	1,718	750
Oil and gas | Gas
Disaggregation of revenue
Revenue from customers	475	235	1,179	727
Oil and gas | Other
Disaggregation of revenue
Revenue from customers	27	23	20	55
Oil and gas | United States
Disaggregation of revenue
Revenue from customers	4,123	2,214	11,027	6,827
Oil and gas | United States | Oil
Disaggregation of revenue
Revenue from customers	3,056	1,784	8,548	5,705
Oil and gas | United States | NGL
Disaggregation of revenue
Revenue from customers	642	252	1,498	592
Oil and gas | United States | Gas
Disaggregation of revenue
Revenue from customers	399	155	963	476
Oil and gas | United States | Other
Disaggregation of revenue
Revenue from customers	26	23	18	54
Oil and gas | International
Disaggregation of revenue
Revenue from customers	933	668	2,436	2,189
Oil and gas | International | Oil
Disaggregation of revenue
Revenue from customers	766	535	1,998	1,779
Oil and gas | International | NGL
Disaggregation of revenue
Revenue from customers	90	53	220	158
Oil and gas | International | Gas
Disaggregation of revenue
Revenue from customers	76	80	216	251
Oil and gas | International | Other
Disaggregation of revenue
Revenue from customers	1	0	2	1
Oil and gas | Eliminations
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and gas | Eliminations | Oil
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and gas | Eliminations | NGL
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and gas | Eliminations | Gas
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and gas | Eliminations | Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
Chemical
Disaggregation of revenue
Revenue from customers	1,395	939	3,669	2,739
Chemical | United States
Disaggregation of revenue
Revenue from customers	1,329	888	3,494	2,591
Chemical | International
Disaggregation of revenue
Revenue from customers	66	51	175	148
Chemical | Eliminations
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and marketing
Disaggregation of revenue
Revenue from customers	690	379	1,792	1,364
Midstream and marketing | United States
Disaggregation of revenue
Revenue from customers	543	244	1,362	986
Midstream and marketing | International
Disaggregation of revenue
Revenue from customers	147	135	430	378
Midstream and marketing | Eliminations
Disaggregation of revenue
Revenue from customers	$ 0	$ 0	$ 0	$ 0