Leases, Total Lease Cost by Class of Underlying Asset (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Finance lease cost:
Amortization of ROU assets	$ 128	$ 54
Interest on lease liabilities	98	50
Lease cost:
Operating lease cost	434	439
Variable lease cost	99	103
Short-term lease cost	91	91
Sublease income	(12)	(30)
Total lease cost	838	707
Pipelines, Terminals, and Tanks [Member]
Finance lease cost:
Amortization of ROU assets	109	44
Interest on lease liabilities	92	47
Lease cost:
Operating lease cost	165	182
Variable lease cost	53	66
Short-term lease cost	9	9
Sublease income	0	0
Total lease cost	428	348
Transportation, Marine [Member]
Finance lease cost:
Amortization of ROU assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	156	145
Variable lease cost	40	35
Short-term lease cost	45	53
Sublease income	(10)	(27)
Total lease cost	231	206
Transportation, Rail [Member]
Finance lease cost:
Amortization of ROU assets	2	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	61	52
Variable lease cost	1	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	64	52
Feedstock Processing Equipment [Member]
Finance lease cost:
Amortization of ROU assets	13	7
Interest on lease liabilities	3	1
Lease cost:
Operating lease cost	15	20
Variable lease cost	3	1
Short-term lease cost	37	29
Sublease income	0	0
Total lease cost	71	58
Energy and Gases [Member]
Finance lease cost:
Amortization of ROU assets	4	3
Interest on lease liabilities	3	2
Lease cost:
Operating lease cost	7	9
Variable lease cost	0	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	14	14
Real Estate [Member]
Finance lease cost:
Amortization of ROU assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	26	27
Variable lease cost	2	1
Short-term lease cost	0	0
Sublease income	(2)	(3)
Total lease cost	26	25
Other [Member]
Finance lease cost:
Amortization of ROU assets	0	0
Interest on lease liabilities	0	0
Lease cost:
Operating lease cost	4	4
Variable lease cost	0	0
Short-term lease cost	0	0
Sublease income	0	0
Total lease cost	$ 4	$ 4

Amount of interest expense on finance lease liability.

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Amount of sublease income excluding finance and operating lease expense.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Lease, Cost, Finance Lease [Abstract]

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