Revenue - Disaggregation of revenue (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
Revenue from customers	$ 3,308	$ 3,731	$ 8,558	$ 7,166
United States
Disaggregation of revenue
Revenue from customers	2,619	2,609	7,058	5,060
Middle East / Africa
Disaggregation of revenue
Revenue from customers	583	1,052	1,439	2,057
Latin America
Disaggregation of revenue
Revenue from customers	103	257	292	439
Other International
Disaggregation of revenue
Revenue from customers	165	18	130	37
Eliminations
Disaggregation of revenue
Revenue from customers	(162)	(205)	(361)	(427)
Eliminations | United States
Disaggregation of revenue
Revenue from customers	0	0	0	0
Eliminations | Middle East / Africa
Disaggregation of revenue
Revenue from customers	0	0	0	0
Eliminations | Latin America
Disaggregation of revenue
Revenue from customers	0	0	0	0
Eliminations | Other International
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas
Disaggregation of revenue
Revenue from customers	2,033	2,718	6,134	5,069
Oil and Gas | Oil
Disaggregation of revenue
Revenue from customers	1,621	2,484	5,165	4,582
Oil and Gas | NGL
Disaggregation of revenue
Revenue from customers	167	152	445	295
Oil and Gas | Gas
Disaggregation of revenue
Revenue from customers	224	89	492	219
Oil and Gas | Other
Disaggregation of revenue
Revenue from customers	21	(7)	32	(27)
Oil and Gas | United States
Disaggregation of revenue
Revenue from customers	1,451	1,538	4,613	2,847
Oil and Gas | United States | Oil
Disaggregation of revenue
Revenue from customers	1,166	1,447	3,921	2,652
Oil and Gas | United States | NGL
Disaggregation of revenue
Revenue from customers	127	84	340	162
Oil and Gas | United States | Gas
Disaggregation of revenue
Revenue from customers	138	8	321	55
Oil and Gas | United States | Other
Disaggregation of revenue
Revenue from customers	20	(1)	31	(22)
Oil and Gas | Middle East / Africa
Disaggregation of revenue
Revenue from customers	512	963	1,297	1,866
Oil and Gas | Middle East / Africa | Oil
Disaggregation of revenue
Revenue from customers	389	825	1,029	1,583
Oil and Gas | Middle East / Africa | NGL
Disaggregation of revenue
Revenue from customers	40	68	105	133
Oil and Gas | Middle East / Africa | Gas
Disaggregation of revenue
Revenue from customers	82	76	162	155
Oil and Gas | Middle East / Africa | Other
Disaggregation of revenue
Revenue from customers	1	(6)	1	(5)
Oil and Gas | Latin America
Disaggregation of revenue
Revenue from customers	70	217	224	356
Oil and Gas | Latin America | Oil
Disaggregation of revenue
Revenue from customers	66	212	215	347
Oil and Gas | Latin America | NGL
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Latin America | Gas
Disaggregation of revenue
Revenue from customers	4	5	9	9
Oil and Gas | Latin America | Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Other International
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Other International | Oil
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Other International | NGL
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Other International | Gas
Disaggregation of revenue
Revenue from customers	0	0	0	0
Oil and Gas | Other International | Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
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	839	993	1,800	2,048
Chemical | United States
Disaggregation of revenue
Revenue from customers	793	935	1,703	1,928
Chemical | Middle East / Africa
Disaggregation of revenue
Revenue from customers	0	0	0	0
Chemical | Latin America
Disaggregation of revenue
Revenue from customers	33	40	68	83
Chemical | Other International
Disaggregation of revenue
Revenue from customers	13	18	29	37
Chemical | Eliminations
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing
Disaggregation of revenue
Revenue from customers	598	225	985	476
Midstream and Marketing | Gas Processing
Disaggregation of revenue
Revenue from customers	138	193	314	400
Midstream and Marketing | Marketing
Disaggregation of revenue
Revenue from customers	451	3	646	5
Midstream and Marketing | Power and Other
Disaggregation of revenue
Revenue from customers	9	29	25	71
Midstream and Marketing | United States
Disaggregation of revenue
Revenue from customers	375	136	742	285
Midstream and Marketing | United States | Gas Processing
Disaggregation of revenue
Revenue from customers	67	104	172	209
Midstream and Marketing | United States | Marketing
Disaggregation of revenue
Revenue from customers	299	3	545	5
Midstream and Marketing | United States | Power and Other
Disaggregation of revenue
Revenue from customers	9	29	25	71
Midstream and Marketing | Middle East / Africa
Disaggregation of revenue
Revenue from customers	71	89	142	191
Midstream and Marketing | Middle East / Africa | Gas Processing
Disaggregation of revenue
Revenue from customers	71	89	142	191
Midstream and Marketing | Middle East / Africa | Marketing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Middle East / Africa | Power and Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Latin America
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Latin America | Gas Processing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Latin America | Marketing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Latin America | Power and Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Other International
Disaggregation of revenue
Revenue from customers	152	0	101	0
Midstream and Marketing | Other International | Gas Processing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Other International | Marketing
Disaggregation of revenue
Revenue from customers	152	0	101	0
Midstream and Marketing | Other International | Power and Other
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Eliminations
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Eliminations | Gas Processing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Eliminations | Marketing
Disaggregation of revenue
Revenue from customers	0	0	0	0
Midstream and Marketing | Eliminations | Power and Other
Disaggregation of revenue
Revenue from customers	$ 0	$ 0	$ 0	$ 0