Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues and other income:
Operating Lease, Lease Income, Related Party	$ 743	$ 952	$ 1,196
Income (Loss) from Equity Method Investments	321	(936)	290
Other Income	21	5	12
Related Party Transaction, Other Revenues from Transactions with Related Party	110	102	107
Revenues, Total	10,027	7,569	9,041
Costs and expenses:
Purchases from related parties	1,219	1,116	1,231
Cost, Depreciation and Amortization	1,287	1,377	1,254
Goodwill and Intangible Asset Impairment	42	2,165	1,197
General and Administrative Expense	353	378	388
Restructuring Charges	0	37	0
Taxes, Miscellaneous	120	125	113
Costs and Expenses, Total	6,035	7,358	6,664
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent, Total	3,992	211	2,377
Interest And Other Financial Costs From Related Parties	8	5	11
Interest expense	785	829	851
Other Nonoperating Income (Expense)	86	62	53
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	3,113	(685)	1,462
Income Tax Expense (Benefit)	1	2	0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total	3,112	(687)	1,462
Net Income (Loss) Attributable to Noncontrolling Interest	35	33	28
Income (Loss) Attributable to Predecessor	0	0	401
Net Income (Loss) Attributable to Parent, Total	3,077	(720)	1,033
Net Income (Loss) Allocated to Limited Partners	$ 2,936	$ (842)	$ 935
Limited Partners' Capital Account [Abstract]
Common - basic (in units)	1,027	1,051	906
Common - diluted (in units)	1,027	1,051	907
Rental cost of sales
Costs and expenses:
Labor and Related Expense	$ 136	$ 135	$ 141
Third Party
Revenues and other income:
Operating Lease, Lease Income	376	398	388
Sales-type Lease, Revenue	0	0	0
Marathon Petroleum Corporation [Member]
Revenues and other income:
Sales-type Lease, Revenue	435	152	7
Costs and expenses:
Labor and Related Expense		254
Restructuring Charges	0	37
Marathon Petroleum Corporation [Member] | Rental cost of sales - related parties [Member]
Costs and expenses:
Labor and Related Expense	$ 109	$ 160	$ 165
Limited Partners Common Units
Net Income Attributable To Parent Company Per Limited Partner Unit Basic And Diluted [Abstract]
Common - basic (in USD per unit)	$ 2.86	$ (0.80)	$ 1.00
Common - diluted (in USD per unit)	$ 2.86	$ (0.80)	$ 1.00
Limited Partners' Capital Account [Abstract]
Common - basic (in units)	1,027	1,051	906
Common - diluted (in units)	1,027	1,051	907
Service [Member]
Revenues and other income:
Revenue from Contract with Customer, Excluding Assessed Tax	$ 2,313	$ 2,397	$ 2,498
Revenue from Contract with Customer, Excluding Assessed Tax, Related Parties	3,628	3,580	3,455
Product [Member]
Revenues and other income:
Revenue from Contract with Customer, Excluding Assessed Tax	1,590	636	806
Revenue from Contract with Customer, Excluding Assessed Tax, Related Parties	145	128	142
Oil and Gas, Refining and Marketing [Member]
Costs and expenses:
Cost of Goods and Services Sold	1,184	1,326	1,489
Natural Gas, Midstream [Member]
Costs and expenses:
Cost of Goods and Services Sold	1,585	539	686
Service, Other [Member]
Revenues and other income:
Revenue from Contract with Customer, Excluding Assessed Tax	345	155	140
Series A Preferred Stock [Member] | Preferred Partner [Member]
Costs and expenses:
Net Income (Loss) Attributable to Parent, Total	100	81	81
Dividends, Preferred Stock	100	81	81
Series B Preferred Stock [Member] | Preferred Partner [Member]
Costs and expenses:
Net Income (Loss) Attributable to Parent, Total	41	41	42
Dividends, Preferred Stock	$ 41	$ 41	$ 17