Reportable Segments Table - Revenues (External and Intersegment) by Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues	$ 13,495	$ 14,514	$ 40,493	$ 40,514
Intrastate Transportation And Storage [Member]
Revenues	764	922	2,385	2,610
Investment In Sunoco LP [Member]
Revenues	4,331	4,761	12,498	13,117
Investment In USAC [Member]
Revenues	175	169	520	336
Interstate Transportation and Storage [Member]
Revenues	479	445	1,470	1,187
Midstream [Member]
Revenues	1,580	2,253	4,496	5,741
NGL and refined products transportation and services [Member]
Revenues	2,878	3,063	8,521	8,177
Crude oil transportation and services [Member]
Revenues	4,453	4,438	13,685	12,986
Other Segments [Member]
Revenues	441	525	1,276	1,599
Intersegment Eliminations [Member]
Revenues	(1,606)	(2,062)	(4,358)	(5,239)
Intersegment [Member] \| Intrastate Transportation And Storage [Member]
Revenues	89	76	270	186
Intersegment [Member] \| Investment In Sunoco LP [Member]
Revenues	3	1	4	3
Intersegment [Member] \| Investment In USAC [Member]
Revenues	6	3	15	5
Intersegment [Member] \| Interstate Transportation and Storage [Member]
Revenues	4	5	16	13
Intersegment [Member] \| Midstream [Member]
Revenues	876	1,716	2,792	4,170
Intersegment [Member] \| NGL and refined products transportation and services [Member]
Revenues	607	218	1,181	710
Intersegment [Member] \| Crude oil transportation and services [Member]
Revenues	0	16	0	44
Intersegment [Member] \| Other Segments [Member]
Revenues	21	27	80	108
External Customers [Member] \| Intrastate Transportation And Storage [Member]
Revenues	675	846	2,115	2,424
External Customers [Member] \| Investment In Sunoco LP [Member]
Revenues	4,328	4,760	12,494	13,114
External Customers [Member] \| Investment In USAC [Member]
Revenues	169	166	505	331
External Customers [Member] \| Interstate Transportation and Storage [Member]
Revenues	475	440	1,454	1,174
External Customers [Member] \| Midstream [Member]
Revenues	704	537	1,704	1,571
External Customers [Member] \| NGL and refined products transportation and services [Member]
Revenues	2,271	2,845	7,340	7,467
External Customers [Member] \| Crude oil transportation and services [Member]
Revenues	4,453	4,422	13,685	12,942
External Customers [Member] \| Other Segments [Member]
Revenues	$ 420	$ 498	$ 1,196	$ 1,491