Leases, Total Lease Cost by Class of Underlying Asset (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Finance lease cost:
Amortization of right-of-use (ROU) assets	$ 26	$ 10
Interest on lease liabilities	22	11
Lease cost:
Operating lease cost	109	105
Variable lease cost	36	28
Short-term lease cost	40	23
Sublease income	(6)	(2)
Total lease cost	227	175
Pipelines, Terminals, and Tanks [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	22	8
Interest on lease liabilities	21	10
Lease cost:
Operating lease cost	42	47
Variable lease cost	16	18
Short-term lease cost	4	3
Sublease income	0	0
Total lease cost	105	86
Transportation, Marine [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	39	34
Variable lease cost	18	10
Short-term lease cost	22	14
Sublease income	(6)	(1)
Total lease cost	73	57
Transportation, Rail [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	15	11
Variable lease cost	1	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	16	11
Feedstock Processing Equipment [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	3	1
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	4	7
Variable lease cost	1	0
Short-term lease cost	14	6
Sublease income	0	0
Total lease cost	22	14
Energy and Gases [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	1	1
Interest on lease liabilities	1	1
Lease cost:
Operating lease cost	2	2
Variable lease cost	0	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	4	4
Real Estate [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	6	4
Variable lease cost	0	0
Short-term lease cost	0	0
Sublease income	0	(1)
Total lease cost	6	3
Other [Member]
Finance lease cost:
Amortization of right-of-use (ROU) assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	1	0
Variable lease cost	0	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	$ 1	$ 0