Shell Midstream Partners (SHLX) 10-Q 30 Jul 21 2021 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2021	Jul. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	001-36710
Entity Registrant Name	Shell Midstream Partners, L.P.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-5223743
Entity Address, Address Line One	150 N. Dairy Ashford
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77079
City Area Code	832
Local Phone Number	337-2034
Title of 12(b) Security	Common Units, Representing Limited Partner Interests
Trading Symbol	SHLX
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		393,289,537
Entity Central Index Key	0001610466
Amendment Flag	false
Document Fiscal Year Focus	2021
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q2

UNAUDITED CONSOLIDATED BALANCE

UNAUDITED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 353	$ 320
Accounts receivable – third parties, net	13	20
Accounts receivable – related parties	33	21
Allowance oil	18	9
Prepaid expenses	8	24
Total current assets	425	394
Equity method investments	996	1,013
Property, plant and equipment, net	673	699
Operating lease right-of-use assets	4	4
Other investments	2	2
Contract assets – related parties	225	233
Other assets – related parties	2	2
Total assets	2,327	2,347
Current liabilities
Accounts payable – third parties	7	5
Accounts payable – related parties	14	16
Deferred revenue – third parties	0	4
Deferred revenue – related parties	18	19
Accrued liabilities – third parties	15	10
Accrued liabilities – related parties	19	28
Total current liabilities	73	82
Noncurrent liabilities
Debt payable – related party	2,691	2,692
Operating lease liabilities	4	4
Finance lease liabilities	23	24
Deferred revenue and other unearned income	3	3
Total noncurrent liabilities	2,721	2,723
Total liabilities	2,794	2,805
Commitments and Contingencies (Note 12)
(DEFICIT) EQUITY
Preferred unitholders (50,782,904 units issued and outstanding as of both June 30, 2021 and December 31, 2020)	(1,059)	(1,059)
Financing receivables – related parties	(296)	(298)
Accumulated other comprehensive loss	(9)	(9)
Total partners’ deficit	(469)	(481)
Noncontrolling interests	2	23
Total deficit	(467)	(458)
Total liabilities and deficit	2,327	2,347
Common Units
(DEFICIT) EQUITY
Common unitholders	3,363	3,382
Common Units | Shell Pipeline Company L P
(DEFICIT) EQUITY
Common unitholders	$ (2,468)	$ (2,497)

UNAUDITED CONSOLIDATED BALANC_2

UNAUDITED CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares	Jun. 30, 2021	Dec. 31, 2020
Common unitholders' capital account, units outstanding (in shares)	393,289,537	393,289,537
Shell Pipeline Company L P
Preferred units, issued (in shares)	50,782,904	50,782,904
Preferred units, outstanding (in shares)	50,782,904	50,782,904
Common Units
Common unitholders' capital account, units issued (in shares)	123,832,233	123,832,233
Common unitholders' capital account, units outstanding (in shares)	123,832,233	123,832,233
Common Units | Shell Pipeline Company L P
Common unitholders' capital account, units issued (in shares)	269,457,304	269,457,304
Common unitholders' capital account, units outstanding (in shares)	269,457,304	269,457,304

UNAUDITED CONSOLIDATED STATEMEN

UNAUDITED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenue
Revenue from contract with customer	$ 134	$ 106	$ 259	$ 213
Lease revenue – related parties	14	14	28	28
Total revenue	148	120	287	241
Costs and expenses
Operations and maintenance – third parties	11	10	22	24
Operations and maintenance – related parties	34	33	61	47
Cost of product sold	7	2	11	17
Impairment of fixed assets	0	0	3	0
General and administrative – third parties	1	1	3	4
General and administrative – related parties	12	15	22	27
Depreciation, amortization and accretion	12	13	25	26
Property and other taxes	6	5	11	10
Total costs and expenses	83	79	158	155
Operating income	65	41	129	86
Income from equity method investments	105	109	207	221
Other income	10	11	24	20
Investment and other income	115	120	231	241
Interest income	7	7	15	8
Interest expense	21	24	42	49
Income before income taxes	166	144	333	286
Income tax expense	0	0	0	0
Net income	166	144	333	286
Less: Net income attributable to noncontrolling interests	4	3	8	7
Net income attributable to the Partnership	162	141	325	279
Preferred unitholder’s interest in net income attributable to the Partnership		12	24	12
General partner’s interest in net income attributable to the Partnership	$ 0	0	0	55
Limited Partners’ interest in net income attributable to the Partnership’s common unitholders		$ 129	$ 301	$ 212
Net income per Limited Partner Unit - Basic and Diluted:
Distributions per Limited Partner unit (in dollars per share)	$ 0.3000	$ 0.4600	$ 0.7600	$ 0.9200
Common
Net income per Limited Partner Unit - Basic and Diluted:
Common - basic (in dollars per share)	0.38	0.33	0.76	0.68
Common - diluted (in dollars per share)	$ 0.36	$ 0.32	$ 0.73	$ 0.66
Common units – public
Costs and expenses
Net income	$ 47	$ 41
Weighted average Limited Partner Units outstanding - Basic and Diluted:
Common units - basic (in shares)	123.8	123.8	123.8	123.8
Common units - diluted (in shares)	123.8	123.8	123.8	123.8
Common units – public | Shell Pipeline Company L P
Costs and expenses
Net income	$ 103	$ 88
Common units – SPLC | Shell Pipeline Company L P
Weighted average Limited Partner Units outstanding - Basic and Diluted:
Common units - basic (in shares)	269.5	269.5	269.5	189.5
Common units - diluted (in shares)	320.3	320.3	320.3	214.8
Third Parties | Transportation, Terminaling and Storage Services
Revenue
Revenue from contract with customer	$ 39	$ 27	$ 80	$ 58
Related Parties
Revenue
Lease revenue – related parties	14	14	28	28
Related Parties | Transportation, Terminaling and Storage Services
Revenue
Revenue from contract with customer	86	77	164	146
Related Parties | Product Revenue
Revenue
Revenue from contract with customer	$ 9	$ 2	$ 15	$ 9

UNAUDITED CONSOLIDATED STATEM_2

UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net income	$ 333	$ 286
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	25	26
Amortization of contract assets - related parties	8	4
Impairment of fixed assets	3	0
Allowance oil reduction to net realizable value	0	8
Undistributed equity earnings	(10)	(1)
Changes in operating assets and liabilities
Accounts receivable	(5)	(4)
Allowance oil	(9)	(1)
Prepaid expenses and other assets	16	10
Accounts payable	0	13
Deferred revenue and other unearned income	(5)	9
Accrued liabilities	(5)	4
Net cash provided by operating activities	351	354
Cash flows from investing activities
Capital expenditures	(4)	(9)
May 2021 Transaction	10	0
Contributions to investment	(3)	0
Return of investment	30	32
Auger Divestiture	2	0
Net cash provided by investing activities	35	23
Cash flows from financing activities
Payment of equity issuance costs	0	(2)
Distributions to noncontrolling interests	(7)	(9)
Distributions to unitholders and general partner	(346)	(325)
Prepayment fee on credit facility	(2)	0
Receipt of principal payments on financing receivables	2	1
Net cash used in financing activities	(353)	(335)
Net increase in cash and cash equivalents	33	42
Cash and cash equivalents at beginning of the period	320	290
Cash and cash equivalents at end of the period	353	332
Non-cash investing and financing transactions:
Change in accrued capital expenditures	1	0
Other non-cash contributions from Parent	$ 0	$ 1

UNAUDITED CONSOLIDATED STATEM_3

UNAUDITED CONSOLIDATED STATEMENT OF CHANGES IN (DEFICIT) EQUITY - USD ($) $ in Millions	Total	Financing Receivables	Accumulated Other Comprehensive Loss	Noncontrolling Interests	Preferred PartnerShell Pipeline Company L P	Common Unitholders	Common UnitholdersShell Pipeline Company L P	General Partner SPLCShell Pipeline Company L P
Beginning balance at Dec. 31, 2019	$ (749)	$ 0	$ (8)	$ 26	$ 0	$ 3,450	$ (203)	$ (4,014)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	142			4		44	39	55
Distributions to unitholders	(162)					(57)	(50)	(55)
Distributions to noncontrolling interests	(5)			(5)
Ending balance at Mar. 31, 2020	(774)	0	(8)	25	0	3,437	(214)	(4,014)
Beginning balance at Dec. 31, 2019	(749)	0	(8)	26	0	3,450	(203)	(4,014)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	286
Ending balance at Jun. 30, 2020	(379)	(301)	(8)	24	(1,059)	3,421	(2,456)	0
Beginning balance at Mar. 31, 2020	(774)	0	(8)	25	0	3,437	(214)	(4,014)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	144			3	12	41	88
Other contributions from Parent	1						1	0
Distributions to unitholders	(163)					(57)	(51)	(55)
Distributions to noncontrolling interests	(4)			(4)
Principal repayments on financing receivables	1	1
April 2020 Transaction	416	(302)			(1,071)		(2,280)	4,069
Ending balance at Jun. 30, 2020	(379)	(301)	(8)	24	(1,059)	3,421	(2,456)	$ 0
Beginning balance at Dec. 31, 2020	(458)	(298)	(9)	23	(1,059)	3,382	(2,497)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	167			4	12	48	103
Distributions to unitholders	(173)				(12)	(57)	(104)
Distributions to noncontrolling interests	(4)			(4)
Principal repayments on financing receivables	1	1
Ending balance at Mar. 31, 2021	(467)	(297)	(9)	23	(1,059)	3,373	(2,498)
Beginning balance at Dec. 31, 2020	(458)	(298)	(9)	23	(1,059)	3,382	(2,497)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	333
Ending balance at Jun. 30, 2021	(467)	(296)	(9)	2	(1,059)	3,363	(2,468)
Beginning balance at Mar. 31, 2021	(467)	(297)	(9)	23	(1,059)	3,373	(2,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	166			4	12	47	103
Distributions to unitholders	(173)				(12)	(57)	(104)
Distributions to noncontrolling interests	(3)			(3)
May 2021 Transaction	9			(22)			31
Principal repayments on financing receivables	1	1
Ending balance at Jun. 30, 2021	$ (467)	$ (296)	$ (9)	$ 2	$ (1,059)	$ 3,363	$ (2,468)

UNAUDITED CONSOLIDATED STATEM_4

UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 166	$ 144	$ 333	$ 286
Other comprehensive loss, net of tax:
Remeasurements of pension and other postretirement benefits related to equity method investments, net of tax	0	0	0	0
Comprehensive income	166	144	333	286
Less comprehensive income attributable to noncontrolling interests	4	3	8	7
Comprehensive income attributable to the Partnership	$ 162	$ 141	$ 325	$ 279

Description of the Business and

Description of the Business and Basis of Presentation	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business and Basis of Presentation	Description of the Business and Basis of Presentation Shell Midstream Partners, L.P. (“we,” “us,” “our,” “SHLX” or “the Partnership”) is a Delaware limited partnership formed by Royal Dutch Shell plc on March 19, 2014 to own and operate pipeline and other midstream assets, including certain assets purchased from Shell Pipeline Company LP (“SPLC”) and its affiliates. We conduct our operations either through our wholly owned subsidiary Shell Midstream Operating LLC (“Operating Company”) or through direct ownership. Our general partner is Shell Midstream Partners GP LLC (“general partner”). References to “RDS,” “Shell” or “Parent” refer collectively to Royal Dutch Shell plc and its controlled affiliates, other than us, our subsidiaries and our general partner. Until April 1, 2020, our general partner owned an approximate 2% general partner economic interest in the Partnership, including the incentive distribution rights (“IDRs”). On April 1, 2020, we closed the transactions contemplated by the Partnership Interests Restructuring Agreement with our general partner dated February 27, 2020 (the “Partnership Interests Restructuring Agreement”), pursuant to which the IDRs were eliminated and the 2% general partner economic interest was converted into a non-economic general partner interest in the Partnership. As of June 30, 2021, our general partner holds a non-economic general partner interest in the Partnership, and affiliates of SPLC own a 68.5% limited partner interest (269,457,304 common units), as well as 50,782,904 Series A perpetual convertible preferred un its (the “Series A Preferred Units”) in the Partnership. These common units and preferred units, on an as-converted basis, represent a 72% interest in the Partnership. See Note 2 — Acquisitions and Other Transactions and Note 8 — (Deficit) Equity for additional details. Description of the Business We own, operate, develop and acquire pipelines and other midstream and logistics assets. As of June 30, 2021, our assets include interests in entities that own (a) crude oil and refined products pipelines and terminals that serve as key infrastructure to transport onshore and offshore crude oil production to Gulf Coast and Midwest refining markets and deliver refined products from those markets to major demand centers and (b) storage tanks and financing receivables that are secured by pipelines, storage tanks, docks, truck and rail racks and other infrastructure used to stage and transport intermediate and finished products. The Partnership’s assets also include interests in entities that own natural gas and refinery gas pipelines that transport offshore natural gas to market hubs and deliver refinery gas from refineries and plants to chemical sites along the Gulf Coast. We generate revenue from the transportation, terminaling and storage of crude oil, refined products, and intermediate and finished products through our pipelines, storage tanks, docks, truck and rail racks, generate income from our equity and other investments, and generate interest income from financing receivables on certain logistic assets. Our operations consist of one reportable segment. The following table reflects our ownership interests as of June 30, 2021: SHLX Ownership Pecten Midstream LLC (“Pecten”) 100.0 % Sand Dollar Pipeline LLC (“Sand Dollar”) 100.0 % Triton West LLC (“Triton”) 100.0 % Zydeco Pipeline Company LLC (“Zydeco”) (1) 100.0 % Mattox Pipeline Company LLC (“Mattox”) 79.0 % Amberjack Pipeline Company LLC (“Amberjack”) – Series A/Series B 75.0% / 50.0% Mars Oil Pipeline Company LLC (“Mars”) 71.5 % Odyssey Pipeline L.L.C. (“Odyssey”) 71.0 % Bengal Pipeline Company LLC (“Bengal”) 50.0 % Crestwood Permian Basin LLC (“Permian Basin”) 50.0 % LOCAP LLC (“LOCAP”) 41.48 % Explorer Pipeline Company (“Explorer”) 38.59 % Poseidon Oil Pipeline Company, L.L.C. (“Poseidon”) 36.0 % Colonial Enterprises, Inc. (“Colonial”) 16.125 % Proteus Oil Pipeline Company, LLC (“Proteus”) 10.0 % Endymion Oil Pipeline Company, LLC (“Endymion”) 10.0 % Cleopatra Gas Gathering Company, LLC (“Cleopatra”) 1.0 % (1) Prior to May 1, 2021, we owned a 92.5% ownership interest in Zydeco and SPLC owned the remaining 7.5% ownership interest. Effective May 1, 2021, SPLC transferred its 7.5% ownership interest to us as part of the May 2021 Transaction. Refer to Note 2 —Acquisitions and Other Transactions for additional information. Basis of Presentation Our unaudited consolidated financial statements include all subsidiaries required to be consolidated under generally accepted accounting principles in the United States (“GAAP”). Our reporting currency is U.S. dollars, and all references to dollars are U.S. dollars. The accompanying unaudited consolidated financial statements and related notes have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by GAAP for complete annual financial statements. The year-end consolidated balance sheet data was derived from audited financial statements. During interim periods, we follow the accounting policies disclosed in our Annual Report on Form 10-K for the year ended December 31, 2020 (our “2020 Annual Report”), filed with the United States Securities and Exchange Commission (“SEC”) unless otherwise described herein. The unaudited consolidated financial statements for the three and six months ended June 30, 2021 and June 30, 2020 include all adjustments we believe are necessary for a fair statement of the results of operations for the interim periods presented. These adjustments are of a normal recurring nature unless otherwise disclosed. Operating results for the interim periods are not necessarily indicative of the results that may be expected for the full year. These unaudited consolidated financial statements and other information included in this Quarterly Report on Form 10-Q should be read in conjunction with our audited consolidated financial statements and notes thereto included in our 2020 Annual Report. Our consolidated subsidiaries include Pecten, Sand Dollar, Triton, Zydeco, Odyssey and the Operating Company. Asset acquisitions of additional interests in previously consolidated subsidiaries and interests in equity method and other investments are included in the financial statements prospectively from the effective date of each acquisition. In cases where these types of acquisitions are considered acquisitions of businesses under common control, the financial statements are retrospectively adjusted. Summary of Significant Accounting Policies The accounting policies are set forth in Note 2 — Summary of Significant Accounting Policies in the Notes to Consolidated Financial Statements of our 2020 Annual Report. There have been no significant changes to these policies during the six months ended June 30, 2021, other than those noted below. Reclassifications Certain amounts for the three and six months ended June 30, 2020 have been reclassified for consistency with current presentation. These reclassifications had no effect on the reported net income. Recent Accounting Pronouncements Standards Adopted as of January 1, 2021

Acquisitions and Other Transact

Acquisitions and Other Transactions	6 Months Ended
	Jun. 30, 2021
Asset Acquisition [Abstract]
Acquisitions and Other Transactions	Acquisitions and Other Transactions May 2021 Transaction Effective May 1, 2021, Triton sold to Equilon Enterprises LLC d/b/a Shell Oil Products US (“SOPUS”), as designee of SPLC, substantially all of the assets associated with its clean products truck rack terminal and facility in Anacortes, Washington (the “Anacortes Assets”). In exchange for the Anacortes Assets, SPLC paid Triton $10 million in cash and transferred to the Operating Company, as designee of Triton, SPLC’s 7.5% interest in Zydeco (the “May 2021 Transaction”). Effective May 1, 2021, the Partnership owns a 100.0% ownership interest in Zydeco. The May 2021 Transaction closed pursuant to a Sale and Purchase Agreement dated April 28, 2021 between Triton and SPLC, effective May 1, 2021 (the “May 2021 Sale and Purchase Agreement”). The May 2021 Sale and Purchase Agreement contains customary representations, warranties and covenants of Triton and SPLC. SPLC, on the one hand, and Triton, on the other hand, have agreed to indemnify each other and their respective affiliates, officers, directors and other representatives against certain losses resulting from any breach of their representations, warranties or covenants contained in the May 2021 Sale and Purchase Agreement, subject to certain limitations and survival periods. In connection with the May 2021 Transaction, the Partnership and SPLC entered into a Termination of Voting Agreement dated April 28, 2021 and effective May 1, 2021, under which they agreed to terminate the Voting Agreement dated November 3, 2014 between the Partnership and SPLC, relating to certain governance matters for their respective direct and indirect ownership interests in Zydeco. Auger Divestiture On January 25, 2021, we executed an agreement to divest the 12” segment of the Auger pipeline; however, this agreement was subsequently terminated. As a result of the intended divestment, we recorded an impairment charge of approximately $3 million during the first quarter of 2021. On April 29, 2021, we executed a new agreement to divest this segment of pipeline, effective June 1, 2021. We received approximately $2 million in cash consideration for this sale. The remainder of the Auger pipeline continues to operate under the ownership of Pecten. April 2020 Transaction On April 1, 2020, we closed the following transactions (together referred to as the “April 2020 Transaction”): • Pursuant to a Purchase and Sale Agreement dated as of February 27, 2020 (the “Purchase and Sale Agreement”) between the Partnership and Triton, SPLC, Shell GOM Pipeline Company LLC (“SGOM”), Shell Chemical LP (“Shell Chemical”) and SOPUS, we acquired 79% of the issued and outstanding membership interests in Mattox from SGOM (the “Mattox Transaction”), and SOPUS and Shell Chemical transferred to Triton, as a designee of the Partnership, certain logistics assets at the Shell Norco Manufacturing Complex located in Norco, Louisiana (such assets, the “Norco Assets,” and such transaction, the “Norco Transaction”); and • Simultaneously with the closing of the transactions contemplated by the Purchase and Sale Agreement, we also closed the transactions contemplated by the Partnership Interests Restructuring Agreement, pursuant to which we eliminated all of the IDRs and converted the 2% economic general partner interest in the Partnership into a non-economic general partner interest (the “GP/IDR Restructuring”). Our general partner or its assignee also agreed to waive a portion of the distributions that would otherwise be payable on the common units issued to SPLC as part of the April 2020 Transaction, in an amount of $20 million per quarter for each of four consecutive fiscal quarters, beginning with the distribution made with respect to the second quarter of 2020 and ending with the distribution made with respect to the first quarter of 2021. As consideration for the April 2020 Transaction, the Partnership issued 50,782,904 Series A Preferred Units to SPLC at a price of $23.63 per unit, plus 160,000,000 newly-issued common units. Certain third-party fair value appraisals were performed to determine the fair value of the total consideration, as well as the fair values of each of the Mattox Transaction, the Norco Transaction and the GP/IDR Restructuring, as of April 1, 2020. Because the components of the April 2020 Transaction were entered in contemplation of each other and were transactions among entities under common control, the fair values of the April 2020 Transaction were used solely for the purpose of allocating a portion of the consideration on a relative fair value basis to the Norco Transaction. In connection with the April 2020 Transaction, the Partnership recorded the following balances as of April 1, 2020: Equity method investment (1) $ 174 Financing receivables – related parties (2) 302 Contract assets - related parties (3) 244 April 2020 Transaction $ 720 (1) Equity method investment was recorded at SGOM’s historical carrying value of the 79% interest in Mattox. See more discussion in the section entitled “Mattox Transaction” below. (2) Financing receivables under the failed sale leaseback were recorded at the fair value of the property, plant and equipment of the Norco Assets transferred by SOPUS and Shell Chemical and recognized as a component of the Partners’ deficit. See more discussion in the section entitled “Norco Transaction” below. (3) Contract assets were recorded based on the difference between the consideration allocated to the Norco Transaction and the financing receivables. See more discussion in the section entitled “Norco Transaction” below. Mattox Transaction We acquired 79% of the issued and outstanding membership interests in Mattox from SGOM. The acquisition was accounted for as a transaction among entities under common control on a prospective basis as an asset acquisition. As a result of the Mattox Transaction, we have significant influence, but not control, over Mattox and account for this investment as an equity method investment. As such, we recorded the acquired equity interests in Mattox at SGOM’s historical carrying value of $174 million, which is included in Equity method investments in our consolidated balance sheet as of June 30, 2021. See Note 4 —Equity Method Investments for additional details. Norco Transaction SOPUS and Shell Chemical transferred certain logistics assets at the Shell Norco Manufacturing Complex located in Norco, Louisiana, which are comprised of crude, chemicals, intermediate and finished product pipelines, storage tanks, docks, truck and rail racks and supporting infrastructure, to Triton, as a designee of the Partnership. The Partnership is treated for accounting purposes as simultaneously leasing the Norco Assets back to SOPUS and Shell Chemical pursuant to the terminaling services agreements entered into among Triton, SOPUS and Shell Chemical related to the Norco Assets. The Partnership receives an annual net payment of $140 million, which is the total annual payment pursuant to the terminaling services agreements of $151 million, less $11 million, which primarily represents the allocated utility costs from SOPUS related to the Norco Assets. Both payments are subject to annual Consumer Price Index adjustments. The transfer of the Norco Assets combined with the terminaling services agreements were accounted for as a failed sale leaseback under ASC Topic 842, Leases (“the lease standard”) , as control of the assets did not transfer to the Partnership. As a result, the transaction was treated as a financing arrangement. As the Norco Transaction was entered into simultaneously and in contemplation of the Mattox Transaction and the GP/IDR Restructuring components, we allocated $546 million of the fair value of the consideration of the April 2020 Transaction to the Norco Transaction based on its relative stand-alone fair value to the other components of the April 2020 Transaction. From this amount, we recorded financing receivables of $302 million, based on the fair value of the Norco Assets’ property, plant and equipment transferred from SOPUS and Shell Chemical, using a combination of market and cost valuation approaches. The financing receivables were recorded as the fair value of property, plant and equipment because the annual payments received by the Partnership are directly related to the lease of the property, plant and equipment of the Norco Assets. Since the financing receivables from SOPUS and Shell Chemical arose from transactions involving the issuance of the Partnership’s common and preferred units, the financing receivables are presented as a component of (deficit) equity and not as assets on the balance sheet. As of April 1, 2020, we also recorded contract assets in the amount of $244 million, which represent the difference between the allocated fair value of the Norco Transaction of $546 million and the recognized financing receivables of $302 million. The contract assets represent the excess of the fair value embedded within the terminaling services agreements transferred by the Partnership to SOPUS and Shell Chemical as part of entering into the terminaling services agreements. See Note 9 — Revenue Recognition for additional details. The amount of contract assets recognized was dependent on the allocated fair value of the consideration to the Norco Transaction, which was determined using the fair values of the consideration transferred and the fair values of each of the three components of the April 2020 Transaction. The newly-issued common units were valued using a market approach based on the market opening price of the Partnership’s common units as of April 1, 2020, less a discount for the waiver described above and a marketability discount. The Series A Preferred Units were valued using an income approach based on a trinomial lattice model. Further, the fair values of the three components of the April 2020 Transaction were determined using an income approach of discounted cash flows at an average discount rate for each of the Mattox Transaction, the Norco Transaction and the GP/IDR Restructuring components of 14%, 11% and 20%, respectively. GP/IDR Restructuring On April 1, 2020, we also closed the transactions contemplated by the Partnership Interests Restructuring Agreement, which included the elimination of all the IDRs and the cancellation of all of the general partner units, both of which were held by our general partner, and amended and restated our partnership agreement to reflect these and other changes (as so amended, the “Second Amended and Restated Partnership Agreement”). The 2% general partner economic interest was converted into a non-economic general partner interest. Because the components of the April 2020 Transaction were among entities under common control, our general partner’s negative equity balance of $4 billion at April 1, 2020 was transferred to SPLC’s equity accounts, allocated between its holdings of common units and preferred units, based on the relative fair value of the consideration related to the issuance of common units and preferred units in the April 2020 Transaction. Upon the closing of the April 2020 Transaction, the Partnership had 393,289,537 common units outstanding, of which SPLC’s wholly owned subsidiary, Shell Midstream LP Holdings LLC (“LP Holdings”), owned 269,457,304 common units in the Partnership, representing an aggregate 68.5% limited partner interest. The Partnership also had 50,782,904 of Series A Preferred Units outstanding, which are entitled to receive a quarterly distribution of $0.2363 per unit and all of which are owned by LP Holdings. See Note 8 — (Deficit) Equity for additional details.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Related party transactions include transactions with SPLC and Shell, including those entities in which Shell has an ownership interest but does not have control. Partnership Interests Restructuring Agreement On February 27, 2020, we and our general partner entered into the Partnership Interests Restructuring Agreement, effective April 1, 2020, pursuant to which the IDRs were eliminated and the 2% general partner economic interest was converted into a non-economic general partner interest in the Partnership. Refer to Note 2 —Acquisitions and Other Transactions for additional information. Purchase and Sale Agreement On February 27, 2020, we entered into the Purchase and Sale Agreement by and among Triton, SPLC, SGOM, Shell Chemical and SOPUS, effective April 1, 2020, pursuant to which we acquired 79% of the issued and outstanding membership interests in Mattox from SGOM, and SOPUS and Shell Chemical transferred to Triton, as a designee of the Partnership, the Norco Assets. Omnibus Agreement We, our general partner, SPLC and the Operating Company entered into an Omnibus Agreement effective February 1, 2019 (the “2019 Omnibus Agreement”). On February 16, 2021, pursuant to the 2019 Omnibus Agreement, the Board of Directors of our general partner (the “Board”) approved a decrease in the annual general and administrative fee to $10 million for 2021, based on a change in the cost of the services provided. The 2019 Omnibus Agreement addresses, among other things, the following matters: • our payment of an annual general and administrative fee of approximately $10 million for the provision of certain services by SPLC; • our obligation to reimburse SPLC for certain direct or allocated costs and expenses incurred by SPLC on our behalf; and • our obligation to reimburse SPLC for all expenses incurred by SPLC as a result of us becoming and continuing as a publicly-traded entity; we will reimburse our general partner for these expenses to the extent the fees relating to such services are not included in the general and administrative fee. Trade Marks License Agreement We, our general partner and SPLC entered into a Trade Marks License Agreement with Shell Trademark Management Inc. effective as of February 1, 2019. The Trade Marks License Agreement grants us the use of certain Shell trademarks and trade names and expires on January 1, 2024 unless earlier terminated by either party upon 360 days’ notice. Tax Sharing Agreement For a discussion of the Tax Sharing Agreement, see Note 4—Related Party Transactions—Tax Sharing Agreement in the Notes to Consolidated Financial Statements of our 2020 Annual Report. Other Agreements We have entered into several customary agreements with SPLC and Shell. These agreements include pipeline operating agreements, reimbursement agreements and services agreements. See Note 4—Related Party Transactions—Other Agreements in the Notes to Consolidated Financial Statements of our 2020 Annual Report. Partnership Agreement Concurrently with the execution of the Partnership Interests Restructuring Agreement, on April 1, 2020, we executed the Second Amended and Restated Partnership Agreement, which amended and restated the Partnership’s First Amended and Restated Agreement of Limited Partnership dated November 3, 2014 (“First Amended and Restated Partnership Agreement”), as the same was previously amended) in its entirety. Under the Second Amended and Restated Partnership Agreement, the IDRs were eliminated, the economic general partnership interest was converted into a non-economic general partner interest, and our general partner or its assignee agreed to waive a portion of the distributions that would otherwise be payable on the common units issued to SPLC as part of the April 2020 Transaction, in an amount of $20 million per quarter for four consecutive fiscal quarters, beginning with the distribution made with respect to the second quarter of 2020 and ending with the distribution made with respect to the first quarter of 2021. Noncontrolling Interests For Zydeco, there is no noncontrolling interest as of June 30, 2021 as a result of the May 2021 Transaction. Refer to Note 2 — Acquisitions and Other Transactions for additional information. The noncontrolling interest for Zydeco consists of SPLC’s 7.5% retained ownership interest as of December 31, 2020. For Odyssey, noncontrolling interest consists of GEL Offshore Pipeline LLC’s (“GEL”) 29% retained ownership interest as of both June 30, 2021 and December 31, 2020. Other Related Party Balances Other related party balances consist of the following: June 30, 2021 December 31, 2020 Accounts receivable $ 33 $ 21 Prepaid expenses 7 22 Other assets 2 2 Contract assets (1) 225 233 Accounts payable (2) 14 16 Deferred revenue 18 19 Accrued liabilities (3) 19 28 Debt payable (4) 2,691 2,692 Finance lease liability 2 2 Financing receivables (1) 296 298 (1) Contract assets and Financing receivables were recognized in connection with the April 2020 Transaction. Refer to the section entitled “ Sale Leaseback ” below for additional details. Financing receivables were presented as a component of (deficit) equity. (2) Accounts payable reflects amounts owed to SPLC for reimbursement of third-party expenses incurred by SPLC for our benefit. (3) As of June 30, 2021, Accrued liabilities reflects $14 million of accrued interest and $5 million of other accrued liabilities. As of December 31, 2020, Accrued liabilities reflects $16 million of accrued interest and $12 million of other accrued liabilities. Other accrued liabilities are primarily related to the accrued operations and maintenance expenses on the Norco Assets. (4) Debt payable reflects borrowings outstanding after taking into account unamortized debt issuance costs of $3 million and $2 million as of June 30, 2021 and December 31, 2020, respectively. Related Party Credit Facilities We have entered into five credit facilities with Shell Treasury Center (West) Inc. (“STCW”), an affiliate of the Partnership: the 2021 Ten Ten Seven Five Five For definitions and additional information regarding these credit facilities, see Note 6 – Related Party Debt in this report and Note 8 – Related Party Debt in the Notes to Consolidated Financial Statements of our 2020 Annual Report. Related Party Revenues and Expenses We provide crude oil transportation, terminaling and storage services to related parties under long-term contracts. We entered into these contracts in the normal course of our business. Our revenue from related parties for the three and six months ended June 30, 2021 and June 30, 2020 is disclosed in Note 9 – Revenue Recognition . The following table shows related party expenses, including certain personnel costs, incurred by Shell and SPLC on our behalf that are reflected in the accompanying unaudited consolidated statements of income for the indicated periods. Included in these amounts, and disclosed below, is our share of operating and general corporate expenses, as well as the fees paid to SPLC under certain agreements. Three Months Ended June 30, Six Months Ended June 30, 2021 2020 (4) 2021 2020 (4) Allocated operating expenses $ 13 $ 16 $ 27 $ 20 Major maintenance costs (1) 2 3 3 3 Insurance expense (2) 5 5 10 10 Other (3) 14 9 21 14 Operations and maintenance – related parties $ 34 $ 33 $ 61 $ 47 Allocated general corporate expenses $ 7 $ 10 $ 12 $ 17 Management Agreement fee 3 3 5 5 Omnibus Agreement fee 2 2 5 5 General and administrative – related parties $ 12 $ 15 $ 22 $ 27 (1) Major maintenance costs are expensed as incurred in connection with the maintenance services of the Norco Assets. Refer to section entitled “ Sale Leaseback ” below for additional details. (2) The majority of our insurance coverage is provided by a wholly owned subsidiary of Shell. The remaining coverage is provided by third-party insurers. (3) Other expenses primarily relate to salaries and wages, other payroll expenses and special maintenance. (4) Certain amounts for the three and six months ended June 30, 2020 have been reclassified for consistency with current presentation. These reclassifications had no effect on the reported net income. For a discussion of services performed by Shell on our behalf, see Note 1 – Description of Business and Basis of Presentation – Basis of Presentation– Expense Allocations in the Notes to Consolidated Financial Statements of our 2020 Annual Report. Pension and Retirement Savings Plans Employees who directly or indirectly support our operations participate in the pension, postretirement health and life insurance and defined contribution benefit plans sponsored by Shell, which include other Shell subsidiaries. Our share of pension and postretirement health and life insurance costs for the three and six months ended June 30, 2021 were $1 million and $3 million, respectively, and for the three and six months ended June 30, 2020 were $1 million and $3 million, respectively. Our share of defined contribution benefit plan costs for the three and six months ended June 30, 2021 were less than $1 million and $1 million, respectively, and for the three and six months ended June 30, 2020 were less than $1 million and $1 million, respectively. Pension and defined contribution benefit plan expenses are included in either General and administrative – related parties or Operations and maintenance – related parties in the accompanying unaudited consolidated statements of income, depending on the nature of the employee’s role in our operations. Equity and Other Investments We have equity and other investments in various entities. In some cases, we may be required to make capital contributions or other payments to these entities. See Note 4 – Equity Method Investments for additional details. Severance Severance expenses are included in either General and administrative – related parties or Operations and maintenance – related parties, depending on the nature of the employee’s role in our operations. For both the three and six months ended June 30, 2021, these costs were not material. For both the three and six months ended June 30, 2020, we recorded voluntary and involuntary severance costs of $5 million. Sale Leaseback Pursuant to the terminaling services agreements entered into among Triton, SOPUS and Shell Chemical related to the Norco Assets acquired in the April 2020 Transaction, the Partnership receives an annual net payment of $140 million, which is the total annual payment pursuant to the terminaling service agreements of $151 million, less $11 million, which primarily represents the allocated utility costs from SOPUS related to the Norco Assets. Both annual payments are subject to annual Consumer Price Index adjustments. The transfer of the Norco Assets, combined with the terminaling services agreements, were accounted for as a failed sale leaseback under the lease standard. As a result, the transaction was treated as a financing arrangement in which the underlying assets were not recognized in property, plant and equipment of the Partnership as control of the Norco Assets did not transfer to the Partnership, and instead were recorded as financing receivables from SOPUS and Shell Chemical. We recognize interest income on the financing receivables on the basis of an imputed interest rate of 11.1% related to SOPUS and 7.4% related to Shell Chemical. The following table shows the interest income and reduction in the financing receivables for the three and six months ended June 30, 2021: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Interest income $ 7 $ 7 $ 15 $ 7 Reduction in the financing receivables 1 1 2 1 Cash payments for interest income 7 5 15 5 Cash payments on principal of the financing receivables 1 1 2 1 The transfer of the Norco Assets and the terminaling services agreements as a result of the April 2020 Transaction have operation and maintenance service components and major maintenance service components (together “service components”). Consistent with our operating lease arrangements, we allocate a portion of the arrangement’s transaction price to any service components within the scope of ASC Topic 606, Revenue from Contracts with Customers (“the revenue standard”) and defer the revenue, if necessary, until the point at which the performance obligation is met. We present the revenue earned from the service components under the revenue standard within Transportation, terminaling and storage services – related parties in the unaudited consolidated statements of income. See Note 9 – Revenue Recognition

Equity Method Investments

Equity Method Investments	6 Months Ended
	Jun. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments For each of the following investments, we have the ability to exercise significant influence over these investments based on certain governance provisions and our participation in the significant activities and decisions that impact the management and economic performance of the investments. Equity method investments comprise the following as of the dates indicated: June 30, 2021 December 31, 2020 Ownership Investment Amount Ownership Investment Amount Mattox 79.0% $ 160 79.0% $ 163 Amberjack – Series A / Series B 75.0% / 50.0% 367 75.0% / 50.0% 382 Mars 71.5% 149 71.5% 152 Bengal 50.0% 86 50.0% 88 Permian Basin 50.0% 82 50.0% 83 LOCAP 41.48% 15 41.48% 12 Explorer 38.59% 69 38.59% 73 Poseidon 36.0% — 36.0% — Colonial 16.125% 38 16.125% 29 Proteus 10.0% 13 10.0% 14 Endymion 10.0% 17 10.0% 17 $ 996 $ 1,013 For the three and six months ended June 30, 2021, distributions received from equity method investments were $128 million and $251 million, respectively. For the three and six months ended June 30, 2020, distributions received from equity method investments were $135 million and $270 million, respectively. Unamortized differences in the basis of the initial investments and our interest in the separate net assets within the financial statements of the investees are amortized into net income over the remaining useful lives of the underlying assets. The amortization is included in Income from equity method investments. As of June 30, 2021 and December 31, 2020, the unamortized basis differences included in our equity investments were $80 million and $84 million, respectively. For the three and six months ended June 30, 2021, the net amortization expense was $2 million and $4 million, and for the three and six months ended June 30, 2020, the net amortization expense was $2 million and $4 million, respectively. During the first quarter of 2018, the investment amount for Poseidon was reduced to zero due to distributions received that were in excess of our investment balance, and we, therefore, suspended the equity method of accounting for this investment. As we have no commitments to provide further financial support to Poseidon, we have recorded excess distributions in Other income of $10 million and $24 million for the three and six months ended June 30, 2021, respectively, and $9 million and $18 million for the three and six months ended June 30, 2020, respectively. Once our cumulative share of equity earnings becomes greater than the cumulative amount of distributions received, we will resume the equity method of accounting as long as the equity method investment balance remains greater than zero. Earnings from our equity method investments were as follows during the periods indicated: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Mattox (1) $ 15 $ 15 $ 30 $ 15 Amberjack 26 29 55 58 Mars 25 28 54 59 Bengal 2 4 5 9 Explorer 26 10 33 24 Colonial 7 18 22 45 Other (2) 4 5 8 11 $ 105 $ 109 $ 207 $ 221 (1) We acquired an interest in Mattox in April 2020. The acquisition of this interest has been accounted for prospectively. (2) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Effective June 4, 2021, Amberjack executed an agreement to divest a small segment of the Amberjack pipeline that is no longer utilized nor deemed a material component in the operation of the pipeline. As a result of the divestment, Amberjack recorded an impairment charge of approximately $4 million during the three months ended June 30, 2021. Our share of approximately $3 million will impact our Income from equity method investments in our unaudited consolidated statements of income. The remainder of the Amberjack pipeline will continue to operate under its current ownership structure. On June 18, 2021, the board of directors of Colonial elected not to declare a dividend for the three months ended June 30, 2021. Under the lease standard , the adoption date for our equity method investments followed the non-public business entity adoption date of January 1, 2020 for their stand-alone financial statements , with the exception of Permian Basin, which adopted on January 1, 2019. There was no material impact on the Partnership’s consolidated financial statements as a result of the adoption of the lease standard by our equity method investees. Summarized Financial Information The following tables present aggregated selected unaudited income statement data for our equity method investments on a 100% basis. However, during periods in which an acquisition occurs, the selected unaudited income statement data reflects activity from the date of the acquisition. Three Months Ended June 30, 2021 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox $ 22 $ 3 $ 19 $ 19 Amberjack 70 19 51 50 Mars 58 22 36 36 Bengal 12 8 4 4 Explorer 139 51 88 67 Colonial 306 209 97 45 Poseidon 34 9 25 24 Other (1) 53 30 23 21 (1) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Six Months Ended June 30, 2021 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox $ 44 $ 6 $ 38 $ 38 Amberjack 142 36 106 105 Mars 121 44 77 77 Bengal 25 15 10 10 Explorer 208 93 115 88 Colonial 596 342 254 142 Poseidon 76 19 57 55 Other (1) 109 62 47 44 (1) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Three Months Ended June 30, 2020 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox (1) $ 22 $ 3 $ 19 $ 19 Amberjack 74 17 57 56 Mars 61 21 40 40 Bengal 15 8 7 7 Explorer 80 43 37 28 Colonial 348 166 182 116 Poseidon 30 8 22 20 Other (2) 57 29 28 23 (1) Our interest in Mattox was acquired on April 1, 2020. (2) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Six Months Ended June 30, 2020 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox (1) $ 22 $ 3 $ 19 $ 19 Amberjack 150 36 114 113 Mars 133 49 84 84 Bengal 32 15 17 17 Explorer 176 90 86 66 Colonial 749 329 420 285 Poseidon 63 17 46 42 Other (2) 114 56 58 48 (1) Our interest in Mattox was acquired on April 1, 2020. Mattox’s total revenues, total operating expenses and operating income (on a 100% basis) for the six months ended June 30, 2020 were $40 million, $6 million and $34 million, respectively. (2) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Capital Contributions We make capital contributions for our pro-rata interest in Permian Basin to fund capital and other expenditures. For the three and six months ended June 30, 2021, we made capital contributions of approximately $1 million and $3 million, respectively. We did not make any capital contributions during the three and six months ended June 30, 2020.

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 30, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment, net, consists of the following as of the dates indicated: Depreciable June 30, 2021 December 31, 2020 Land — $ 12 $ 12 Building and improvements 10 - 40 years 46 47 Pipeline and equipment (1) 10 - 30 years 1,239 1,263 Other 5 - 25 years 35 34 1,332 1,356 Accumulated depreciation and amortization (2) (666) (661) 666 695 Construction in progress 7 4 Property, plant and equipment, net $ 673 $ 699 (1) As of both June 30, 2021 and December 31, 2020, includes costs of $365 million and $372 million, respectively, related to assets under operating leases (as lessor). As of both June 30, 2021 and December 31, 2020, includes cost of $23 million related to assets under capital lease (as lessee). (2) As of June 30, 2021 and December 31, 2020, includes accumulated depreciation of $148 million and $147 million, respectively, related to assets under operating leases (as lessor). As of both June 30, 2021 and December 31, 2020, includes accumulated amortization of $9 million and $8 million, respectively, related to assets under capital lease (as lessee). Deprec iation and amortization expense on property, plant and equipment for the three and six months ended June 30, 2021 wa s $12 million and $25 million, respectively, and for the three and six months ended June 30, 2020 was $13 million and $26 million, respectively, and is included in costs and expenses in the accompanying unaudited consolidated statements of income. Depreciation and amortization expense on property, plant and equipment includes amounts pertaining to assets under operating (as lessor) and capital (as lessee) leases. May 2021 Transaction Effective May 1, 2021, Triton sold to SOPUS, as designee of SPLC, the Anacortes Assets. In exchange for the Anacortes Assets, SPLC paid Triton $10 million in cash and transferred to the Operating Company, as designee of Triton, SPLC’s 7.5% interest in Zydeco. Effective May 1, 2021, the Partnership owns a 100.0% ownership interest in Zydeco. Refer to Note 2 – Acquisitions and Other Transactions for additional information on this transaction. Auger Divestiture On January 25, 2021, we executed an agreement to divest the 12” segment of the Auger pipeline; however, this agreement was subsequently terminated. As a result of the intended divestment, we recorded an impairment charge of approximately $3 million during the first quarter of 2021. On April 29, 2021, we executed a new agreement to divest this segment of pipeline, effective June 1, 2021. We received approximately $2 million in cash consideration for this sale. The remainder of the Auger pipeline will continue to operate under the ownership of Pecten. Refer to Note 2 – Acquisitions and Other Transactions for additional information on this divestiture.

Related Party Debt

Related Party Debt	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Related Party Debt	Related Party Debt Consolidated related party debt obligations comprise the following as of the dates indicated: June 30, 2021 December 31, 2020 Outstanding Balance Total Capacity Available Capacity Outstanding Balance Total Capacity Available Capacity 2021 Ten $ 600 $ 600 $ — $ — $ — $ — Ten 600 600 — 600 600 — Seven 600 600 — 600 600 — Five 494 760 266 494 760 266 Five 400 1,000 600 400 1,000 600 Five — — — 600 600 — 2019 Zydeco Revolver (1) — — — — 30 30 Unamortized debt issuance costs (3) n/a n/a (2) n/a n/a Debt payable – related party $ 2,691 $ 3,560 $ 866 $ 2,692 $ 3,590 $ 896 (1) The 2019 Zydeco Revolver was terminated effective June 30, 2021. See below for additional information. For the three and six months ended June 30, 2021, interest and fee expenses associated with our borrowings, net of capitalized interest, were $20 million and $41 million, respectively, and for the three and six months ended June 30, 2020, interest and fee expenses associated with our borrowings, net of capitalized interest, were $23 million and $47 million, respectively. We paid $17 million and $41 million for interest, respectively, during the three and six months ended June 30, 2021, and we paid $24 million and $49 million for interest, respectively, during the three and six ended June 30, 2020. On June 30, 2021, Zydeco entered into a termination of revolving loan facility agreement with STCW to terminate the 2019 Zydeco Revolver. Zydeco has not borrowed any funds under this facility, and therefore, no further obligations exist. On March 16, 2021, we entered into a ten-year fixed rate credit facility with STCW with a borrowing capacity of $600 million (the “2021 Ten Ten Ten Ten Ten Ten Five Five Five Borrowings under our revolving credit facilities approximate fair value as the interest rates are variable and reflective of market rates, which results in Level 2 instruments. The fair value of our fixed rate credit facilities is estimated based on the published market prices for issuances of similar risk and tenor and is categorized as Level 2 within the fair value hierarchy. As of June 30, 2021, the carrying amount and estimated fair value of total debt (before amortization of issuance costs) was $2,694 million and $2,898 million, respectively. As of December 31, 2020, the carrying amount and estimated fair value of total debt (before amortization of issuance costs) was $2,694 million and $2,928 million, respectively. Borrowings and repayments under our credit facilities for the six months ended June 30, 2021 and June 30, 2020 are disclosed in our unaudited consolidated statements of cash flows. See Note 8 – (Deficit) Equity for additional information regarding the source of our repayments, if applicable to the period. Borrowings under each of the Five Year Revolver due July 2023 and the Five Year Revolver due December 2022 bear interest at the three-month London Interbank Offered Rate (“LIBOR”) plus a margin or, in certain instances (including if LIBOR is discontinued) at an alternate interest rate as described in each respective revolver. Over the next few years, LIBOR will be discontinued globally, and, as such, a new benchmark will take its place. We are in discussion with our Parent to further clarify the reference rate(s) applicable to our revolving credit facilities once LIBOR is discontinued, and we are evaluating any potential impact on our facilities. For additional information on our credit facilities, refer to Note 8 – Related Party Debt in the Notes to Consolidated Financial Statements in our 2020 Annual Report.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss For both the three and six months ended June 30, 2021, we recorded remeasurements losses of less than $1 million related to the pension and other post-retirement benefits provided by Explorer and Colonial to their employees. For both the three and six

(Deficit) Equity

(Deficit) Equity	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
(Deficit) Equity	(Deficit) Equity General Partner and IDR Restructuring Prior to April 1, 2020, our capital accounts were comprised of a 2% general partner interest and 98% limited partner interests. On April 1, 2020, in connection with the April 2020 Transaction, we closed on the transactions contemplated by the Partnership Interests Restructuring Agreement, pursuant to which we eliminated all of the IDRs and converted the 2% economic general partner interest in the Partnership into a non-economic general partner interest. As a result, 4,761,012 general partner units and the IDRs were canceled and are no longer outstanding, and therefore, no longer participate in distributions of cash from the Partnership. Because the transaction was among entities under common control, our general partner’s negative equity balance of $4 billion at April 1, 2020 was transferred to SPLC’s equity accounts, allocated between its holdings of common units and preferred units, based on the relative fair value of the common units and preferred units issued as consideration in the April 2020 Transaction. Shelf Registrations We have a universal shelf registration statement on Form S-3 on file with the SEC under which we, as a well-known seasoned issuer, have the ability to issue and sell an indeterminate amount of common units and partnership securities representing limited partner units. We also have on file with the SEC a shelf registration statement on Form S-3 relating to $1,000,000,000 of common units and partnership securities representing limited partner units to be used in connection with the “at-the-market” equity distribution program, direct sales or other sales consistent with the plan of distribution set forth in the registration statement. At-the-Market Program We have an “at-the-market” equity distribution program pursuant to which we may issue and sell common units for up to $300 million in gross proceeds. During both the six months ended June 30, 2021 and June 30, 2020, we did not have any sales under this program. Units Outstanding Common units The common units represent limited partner interests in us. The holders of common units, both public and SPLC, are entitled to participate in partnership distributions and have limited rights of ownership as provided for under the Second Amended and Restated Partnership Agreement. As of both June 30, 2021 and December 31, 2020 , we had 393,289,537 common units outstanding, of which 123,832,233 were publicly owned. SPLC owned 269,457,304 common units, representing an aggregate 68.5% limited partner interest in us. Series A Preferred Units As of both June 30, 2021 and December 31, 2020 , we had 50,782,904 preferred units outstanding. On April 1, 2020, as partial consideration for the April 2020 Transaction, we issued 50,782,904 Series A Preferred Units to SPLC at a price of $23.63 per preferred unit. The Series A Preferred Units rank senior to all common units with respect to distribution rights and rights upon liquidation. The Series A Preferred Units have voting rights, distribution rights and certain redemption rights, and are also convertible (at the option of the Partnership and at the option of the holder, in each case under certain circumstances) and are otherwise subject to the terms and conditions as set forth in the Second Amended and Restated Partnership Agreement. We classified the Series A Preferred Units as permanent equity since they are not redeemable for cash or other assets 1) at a fixed or determinable price on a fixed or determinable date; 2) at the option of the holder; or 3) upon the occurrence of an event that is not solely within the control of the issuer. Conversion At the option of Series A Preferred Unitholder s. Beginning with the earlier of (1) January 1, 2022 and (2) immediately prior to the liquidation of the Partnership, the Series A Preferred Units are convertible by the preferred unitholders, at the preferred unitholders ’ option, into common units on a one-for-one basis, adjusted to give effect to any accrued and unpaid distributions on the applicable preferred units. At the option of the Partnership. The Partnership shall have the right to convert the Series A Preferred Units on a one-for-one basis, adjusted to give effect to any accrued and unpaid distributions on the applicable Series A Preferred Units, into common units at any time from and after January 1, 2023, if the closing price of the common units is greater than $33.082 per unit (140% of the Series A Preferred Unit Issue Price (as defined in the Second Amended and Restated Partnership Agreement)) for any 20 trading days during the 30 trading-day period immediately preceding notice of the conversion. The conversion rate for the Series A Preferred Units shall be the quotient of (a) the sum of (i) $23.63, plus (ii) any unpaid cash distributions on the applicable Series A Preferred Units , divided by (b) $23.63. Voting The Series A Preferred Units are entitled to vote on an as-converted basis with the c ommon u nits and have certain other class voting rights with respect to any amendment to the Second Amended and Restated Partnership Agreement . In the event of any liquidation of the Partnership, the Series A Preferred Units are entitled to receive, out of the assets of the Partnership available for distribution to the p artners or any assignees, prior and in preference to any distribution of any assets of any junior securities, the value in each holder ’ s capital account in respect of such Series A Preferred Units. Change of Control U pon the occurrence of certain events involving a change of control in which more than 90% of the consideration payable to the holders of the c ommon u nits is payable in cash, the Series A Preferred Units will automatically convert into c ommon u nits at the then-applicable conversion rate. Upon the occurrence of certain other events involving a change of control, the holders of the Series A Preferred Units may elect, among other potential elections, to convert the Series A Preferred Units to common units at the then-applicable conversion rate. Special Distribution Each Series A Preferred Unit has the right to share in any special distributions by the Partnership of cash, securities or other property pro rata with the common units or any other securities, on an as-converted basis, provided that special distributions shall not include regular quarterly distributions paid in the normal course of business on the common units. Distributions to our Unitholders In connection with the April 2020 Transaction, commencing with the quarter ended June 30, 2020, the holders of the Series A Preferred Units are entitled to cumulative quarterly distributions at a rate of $0.2363 per Series A Preferred Unit, payable quarterly in arrears no later than 60 days after the end of the applicable quarter. The Partnership is not entitled to pay any distributions on any junior securities, including any of the common units, prior to paying the quarterly distribution payable to the Series A Preferred Units, including any previously accrued and unpaid distributions. For the three and six months ended June 30, 2021, the aggregate amounts of cumulative preferred distributions paid were $12 million and $24 million, respectively, and the per unit amount for the three and six months ended June 30, 2021 was $0.2363 and $0.4726, respectively. Under the Second Amended and Restated Partnership Agreement, our general partner or its assignee has agreed to waive a portion of the distributions that would otherwise be payable on the common units issued to SPLC as part of the April 2020 Transaction, in an amount of $20 million per quarter for four consecutive fiscal quarters, beginning with the distribution made with respect to the second quarter of 2020 and ending with the distribution made with respect to the first quarter of 2021. See Note 3 — Related Party Transactions for terms of the Second Amended and Restated Partnership Agreement. The following table details the distributions declared and/or paid for the periods presented: Date Paid or Public SPLC SPLC General Partner Distributions to be Paid Three Months Ended Common Preferred Common IDRs 2% Total (in millions, except per unit amounts) February 14, 2020 December 31, 2019 $ 57 $ — $ 50 $ 52 $ 3 $ 162 $ 0.4600 May 15, 2020 March 31, 2020 57 — 50 52 (2) 3 (3) 162 0.4600 August 14, 2020 June 30, 2020 (1) 57 12 104 — — 173 0.4600 November 13, 2020 September 30, 2020 (1) 57 12 104 — — 173 0.4600 February 12, 2021 December 31, 2020 (1) 57 12 104 — — 173 0.4600 May 14, 2021 March 31, 2021 (1) 57 12 104 — — 173 0.4600 August 13, 2021 June 30, 2021 (4) 37 12 81 — — 130 0.3000 (1) Includes the impact of waived distributions to SPLC with respect to the April 2020 Transaction as described above. (2) This amount represents the Final IDR Payment (as defined in the Partnership Interests Restructuring Agreement) to which our general partner (or its assignee) was entitled pursuant to the Partnership Interests Restructuring Agreement. Also pursuant to the Partnership Interests Restructuring Agreement, our general partner agreed (on its own behalf and on behalf of its assignees) to waive any distributions that it would otherwise be entitled to receive with respect to the newly-issued 160 million common units that it received in the April 2020 Transaction for the quarter in which it receives the Final IDR Payment. Our general partner is not entitled to any payments with respect to the IDRs, as they were cancelled as a part of the April 2020 Transaction. (3) This amount represents the final distribution payment on the 2% economic general partner interest. Our general partner is not entitled to any payments with respect to the economic general partner interest, as it was converted into a non-economic general partner interest as a part of the April 2020 Transaction. (4) See Note 13 — Subsequent Events for additional information. Distributions to Noncontrolling Interests There was no distribution to SPLC for its noncontrolling interest in Zydeco for the three months ended June 30, 2021 as a result of the May 2021 Transaction. Refer to Note 2 — Acquisitions and Other Transactions for additional information. Distributions to SPLC for its noncontrolling interest in Zydeco for the six months ended June 30, 2021 were less than $1 million, and for the three and six months ended June 30, 2020 were $2 million and $3 million, respectively. Distributions to GEL for its noncontrolling interest in Odyssey for the three and six months ended June 30, 2021 were $3 million and $7 million , respectively, and for the three and six months ended June 30, 2020 were $2 million and $6 million, respectively. See Note 3 — Related Party Transactions for additional details.

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition The revenue standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. The revenue standard requires entities to recognize revenue through the application of a five-step model, which includes: identification of the contract; identification of the performance obligations; determination of the transaction price; allocation of the transaction price to the performance obligations; and recognition of revenue as the entity satisfies the performance obligations. Disaggregation of Revenue The following table provides information about disaggregated revenue by service type and customer type: Three Months Ended June 30, Six Months Ended 2021 2020 2021 2020 Transportation services revenue – third parties $ 37 $ 25 $ 76 $ 54 Transportation services revenue – related parties (1) 51 41 95 96 Storage services revenue – third parties 2 2 4 4 Storage services revenue – related parties 2 2 4 4 Terminaling services revenue – related parties (2) 31 30 61 42 Terminaling services revenue – major maintenance service – related parties (3) 2 4 4 4 Product revenue – related parties (4) 9 2 15 9 Total Topic 606 revenue 134 106 259 213 Lease revenue – related parties 14 14 28 28 Total revenue $ 148 $ 120 $ 287 $ 241 (1) Transportation services revenue - related parties includes $1 million and $2 million, respectively, of the non-lease service component in our transportation services contracts for both the three and six months ended June 30, 2021 and 2020. (2) Terminaling services revenue - related parties is comprised of the service components in our terminaling services contracts, including the operation and maintenance service components related to the Norco Assets in connection with the April 2020 Transaction. See N ote 3 – Related Party Transactions for additional details. (3) Terminaling services revenue - major maintenance service - related parties is comprised of the service components related to providing required major maintenance to the Norco Assets in connection with the April 2020 Transaction. See N ote 3 – Related Party Transactions for additional details. (4) Product revenue is comprised of allowance oil sales. Lease revenue Certain of our long-term transportation and terminaling services contracts with related parties are accounted for as operating leases. These agreements have both lease and non-lease service components. We allocate the arrangement consideration between the lease components and any non-lease service components based on the relative stand-alone selling price of each component. We estimate the stand-alone selling price of the lease and non-lease service components based on an analysis of service-related and lease-related costs for each contract, adjusted for a representative profit margin. The contracts have a minimum fixed monthly payment for both the lease and non-lease service components. We present the non-lease service components under the revenue standard within Transportation, terminaling and storage services – related parties in the unaudited consolidated statements of income. Revenues from the lease components of these agreements are recorded within Lease revenue – related parties in the unaudited consolidated statements of income. Some of these agreements were entered into for terms of ten years, with the option for the lessee to extend for two additional five-year terms. One of these contracts was amended to include an option for the lessee to extend for a fourteen-month term prior to the original extension options. However, it is reasonably certain that the original extension options of the two additional five-year terms will not be exercised for this contract. Further, we have agreements with initial terms of ten years with the option for the lessee to extend for up to ten additional one-year terms. As of June 30, 2021, future minimum payments of both the lease and non-lease service components to be received under the ten-year contract term of these operating leases were estimated to be: Total Less than 1 year Years 2 to 3 Years 4 to 5 More than 5 years Operating leases $ 646 $ 105 $ 210 $ 210 $ 121 Terminaling services revenue - Norco Assets In April 2020, the Partnership closed the transaction pursuant to which the Norco Assets were transferred from SOPUS and Shell Chemical to Triton. In connection with closing this transaction, Triton entered into terminaling service agreements with SOPUS and Shell Chemical related to the Norco Assets. These terminaling service agreements were entered into for an initial term of fifteen years, with the option to extend for an additional five-year term. The transfer of the Norco Assets, combined with the terminaling services agreements, were accounted for as a failed sale leaseback under the lease standard. The Partnership receives an annual net payment of $140 million, which is the total annual payment pursuant to the terminaling service agreements of $151 million, less $11 million, which primarily represents the allocated utility costs from SOPUS related to the Norco Assets. These agreements have components related to financing receivables, for which the interest income is recognized in the unaudited consolidated statements of income and principal payments are recognized as a reduction to the financing receivables in the unaudited consolidated balance sheet. Revenue related to the operation and maintenance service components and major maintenance service components are presented within Transportation, terminaling and storage services – related parties in the unaudited consolidated statements of income. The operation and maintenance service components consist of the Partnership’s obligation to operate the Norco Assets over the life of the agreements. It is considered a distinct service that represents a performance obligation that would be satisfied over time if it were accounted for separately. The services provided over the contract period are a series of distinct services that are substantially the same, have the same pattern of transfer to the customer, and, therefore, qualify as a single performance obligation. Since the customer simultaneously receives and consumes the benefits of services, we recognize revenue over time based on the number of days elapsed. The major maintenance service components consist of the Partnership’s obligation to provide major maintenance on the Norco Assets such that the current capacity available to the customers is maintained over the life of the agreements. It is considered a distinct service that represents a performance obligation that would be satisfied over time if it were accounted for separately. The services provided over the contract period are a series of distinct services that are substantially the same, have the same pattern of transfer to the customer, and therefore, qualify as a single performance obligation. Since the customer simultaneously receives and consumes the benefits of services, we recognize revenue over time using the input method (cost-to-cost method) based on the ratio of actual major maintenance costs incurred to date to the total forecasted major maintenance costs over the contract term. We allocate the arrangement consideration between the components based on the relative stand-alone selling price of each component in accordance with the revenue standard . The Partnership established the stand-alone selling price for the financing components based off an expected return on the assets being financed. The Partnership established the stand-alone selling price for the service components using expected cost-plus margin approach based on the Partnership’s forecasted costs of satisfying the performance obligation plus an appropriate margin for the service. The key assumptions include forecasts of the future operation and maintenance costs and major maintenance costs and the expected margin with respect to the service components and the expected return on the assets with respect to the financing components. Contract Balances The following table provides information about receivables and contract liabilities from contracts with customers: January 1, 2021 June 30, 2021 Receivables from contracts with customers – third parties $ 19 $ 11 Receivables from contracts with customers – related parties 18 25 Contract assets – related parties 233 225 Deferred revenue – third parties 4 — Deferred revenue – related parties (1) 19 18 (1) Deferred revenue - related parties is related to deficiency credits from certain minimum volume commitment contracts and certain components of our terminaling service contracts on the Norco Assets. In connection with the April 2020 Transaction, we also recorded contract assets based on the difference between the consideration allocated to the Norco Transaction and the recognized financing receivables. The contract assets represent the excess of the fair value embedded within the terminaling services agreements transferred by the Partnership to SOPUS and Shell Chemical as part of entering into the terminaling services agreements. The contract assets balance is amortized in a pattern consistent with the recognition of revenue on the service components of the contract. The portion of the contract assets relate d to operations and maintenance is amortized on a straight-line basis over a fifteen-year period, and the portion related to major maintenance is amortized based on the ratio of actual major maintenance costs incurred to the total projected major maintenance costs over the fifteen year term. We recorded amortization as a component of Transportation, terminaling and storage services – related parties of $4 million and $8 million, respectively, for the three and six months ended June 30, 2021, and $4 million for both the three and six months ended June 30, 2020. We had $225 million and $233 million contract assets recognized from the costs to obtain or fulfill a contract as of June 30, 2021 and December 31, 2020, respectively. The estimated future amortization related to the contract assets for the next five years is as follows: Remainder of 2021 2022 2023 2024 2025 2026 Amortization $ 8 $ 16 $ 16 $ 17 $ 17 $ 15 Significant changes in the deferred revenue balances with customers during the period are as follows: December 31, 2020 Additions (1) Reductions (2) June 30, 2021 Deferred revenue – third parties $ 4 $ 2 $ (6) $ — Deferred revenue – related parties 19 10 (11) 18 (1) Deferred revenue additions resulted from $6 million deficiency payments from minimum volume commitment contracts and $6 million of deferred revenue related to the major maintenance service components of our terminaling service contracts on the Norco Assets. (2) Deferred revenue reductions resulted from revenue earned through the actual or estimated use and expiration of deficiency credits. Remaining Performance Obligations The following table includes revenue expected to be recognized in the future related to performance obligations exceeding one year of their initial terms that are unsatisfied or partially unsatisfied as of June 30, 2021: Total Remainder of 2021 2022 2023 2024 2025 and beyond Revenue expected to be recognized on multi-year committed shipper transportation contracts $ 442 $ 32 $ 63 $ 63 $ 57 $ 227 Revenue expected to be recognized on other multi-year transportation service contracts (1) 32 3 6 6 4 13 Revenue expected to be recognized on multi-year storage service contracts 23 5 10 4 4 — Revenue expected to be recognized on multi-year terminaling service contracts (1) 286 22 45 45 45 129 Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts (2) 1,464 53 106 106 107 1,092 $ 2,247 $ 115 $ 230 $ 224 $ 217 $ 1,461 (1) Relates to the non-lease service components of certain of our long-term transportation and terminaling service contracts, which are accounted for as operating leases. (2) Relates to the operation and maintenance service components and the major maintenance service components of our terminaling service contracts on the Norco Assets in connection with the April 2020 Transaction. As an exemption under the revenue standard, we do not disclose the amount of remaining performance obligations for contracts with an original expected duration of one year or less or for variable consideration that is allocated entirely to a wholly unsatisfied promise to transfer a distinct service that forms part of a single performance obligation.

Net Income Per Limited Partner

Net Income Per Limited Partner Unit	6 Months Ended
	Jun. 30, 2021
Partners' Capital Notes [Abstract]
Net Income Per Limited Partner Unit	Net Income Per Limited Partner Unit Net income per unit applicable to common limited partner units is computed by dividing the respective limited partners’ interest in net income attributable to the Partnership for the period by the weighted average number of common units outstanding for the period. Prior to April 1, 2020, the classes of participating securities included common units, general partner units and IDRs. Because we had more than one class of participating securities, we used the two-class method when calculating the net income per unit applicable to limited partners. Effective April 1, 2020, the classes of participating securities included only common units, as the general partner units and the IDRs were eliminated and the Series A Preferred Units are not considered a participating security. See Note 8 – (Deficit) Equity , for a discussion of the elimination of our general partner’s IDRs and 2% economic interest effective April 1, 2020. For the three and six months ended June 30, 2021 and June 30, 2020, our Series A Preferred Units were dilutive to net income per limited partner unit. Net income earned by the Partnership is allocated between the classes of participating securities in accordance with the terms of our partnership agreement as in effect on the date such calculation is performed, after giving effect to priority income allocations to the holders of the Series A Preferred Units, if applicable. Earnings are allocated based on actual cash distributions declared to our unitholders, including those attributable to the IDRs prior to the second quarter of 2020, if applicable. To the extent net income attributable to the Partnership exceeds or is less than cash distributions, this difference is allocated based on the unitholders’ respective ownership percentages. For the diluted net income per limited partner unit calculation under the Second Amended and Restated Partnership Agreement, the Series A Preferred Units are assumed to be converted at the beginning of the period into common limited partner units o n a one-for-one basis, and the distribution formula for available cash is recalculated using the available cash amount increased only for the preferred distributions, which would have been attributable to the common units after conversion. The following tables show the allocation of net income attributable to the Partnership to arrive at net income per limited partner unit: Three Months Ended June 30, Six Months Ended 2021 (1) 2020 (1) 2021 (1) 2020 Net income * * * $ 286 Less: Net income attributable to noncontrolling interests * * * 7 Net income attributable to the Partnership * * * 279 Less: General partner’s distribution declared * * * 55 Preferred unitholder’s interest in net income * * * 12 Limited partners’ distribution declared on common units * * * 268 Distributions in excess of income * * * $ (56) (1) Effective April 1, 2020, the classes of participating securities included only common units, as the general partner units and the IDRs were eliminated and the Series A Preferred Units are not considered a participating security. Therefore, the allocation of net income attributable to the Partnership to arrive at net income per limited partner unit is not applicable for the three and six months ended June 30, 2021, nor to the three months ended June 30, 2020. Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Limited Partners’ Common Units (in millions of dollars, except per unit data) Net income attributable to the Partnership’s common unitholders (basic) $ 150 $ 301 Dilutive effect of preferred units 12 24 Net income attributable to the Partnership’s common unitholders (diluted) $ 162 $ 325 Weighted average units outstanding - Basic 393.3 393.3 Dilutive effect of preferred units 50.8 50.8 Weighted average units outstanding - Diluted 444.1 444.1 Net income per limited partner unit: Basic $ 0.38 $ 0.76 Diluted $ 0.36 $ 0.73 Three Months Ended June 30, 2020 Limited Partners’ Common Units (in millions of dollars, except per unit data) Net income attributable to the Partnership’s common unitholders (basic) $ 129 Dilutive effect of preferred units 12 Net income attributable to the Partnership’s common unitholders (diluted) $ 141 Weighted average units outstanding - Basic 393.3 Dilutive effect of preferred units 50.8 Weighted average units outstanding - Diluted 444.1 Net income per limited partner unit: Basic $ 0.33 Diluted $ 0.32 Six Months Ended June 30, 2020 General Partner Limited Partners’ Common Units Total (in millions of dollars, except per unit data) Distributions declared $ 55 $ 268 $ 323 Distributions in excess of income — (56) (56) Net income attributable to the Partnership's common unitholders (basic) $ 55 $ 212 $ 267 Dilutive effect of preferred units 12 Net income attributable to the Partnership's common unitholders (dilutive) $ 224 Weighted average units outstanding - Basic 313.3 Dilutive effect of preferred units 25.4 Weighted average units outstanding - Diluted 338.7 Net income per limited partner unit: Basic $ 0.68 Diluted $ 0.66

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We are not a taxable entity for U.S. federal income tax purposes or for the majority of states that impose an income tax. Taxes on our net income are generally borne by our partners through the allocation of taxable income. Our income tax expense results from partnership activity in the state of Texas, as conducted by Zyd eco, Sand Dollar and Triton. Income tax expense for both the three and six months ended June 30, 2021 and June 30, 2020 was not material.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Environmental Matters We are subject to federal, state and local environmental laws and regulations. We routinely conduct reviews of potential environmental issues and claims that could impact our assets or operations. These reviews assist us in identifying environmental issues and estimating the costs and timing of remediation efforts. In making environmental liability estimations, we consider the material effect of environmental compliance, pending legal actions against us and potential third-party liability claims. Often, as the remediation evaluation and effort progresses, additional information is obtained, requiring revisions to estimated costs. These revisions are reflected in our income in the period in which they are probable and reasonably estimable. As of both June 30, 2021 and December 31, 2020, these costs and any related liabilities are not material. Legal Proceedings We are named defendants in lawsuits and governmental proceedings that arise in the ordinary course of business. For each of our outstanding legal matters, we evaluate the merits of the case, our exposure to the matter, possible legal or settlement strategies and the likelihood of an unfavorable outcome. While there are still uncertainties related to the ultimate costs we may incur, based upon our evaluation and experience to date, we do not expect that the ultimate resolution of these matters will have a material adverse effect on our financial position, operating results or cash flows. Other Commitments Odyssey entered into a tie-in agreement effective January 2012 with a third party, which allowed producers to install the tie-in connection facilities and tying into the system. The agreement will continue to be in effect until the continued operation of the platform is uneconomic. We hold cancellable easements or rights-of-way arrangements from landowners permitting the use of land for the construction and operation of our pipeline systems. Obligations under these easements are not material to the results of our operations.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events We have evaluated events that occurred after June 30, 2021 through the issuance of these unaudited consolidated financial statements. Any material subsequent events that occurred during this time have been properly recognized or disclosed in the unaudited consolidated financial statements and accompanying notes. Distribution

Description of the Business a_2

Description of the Business and Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business	Description of the Business We own, operate, develop and acquire pipelines and other midstream and logistics assets. As of June 30, 2021, our assets include interests in entities that own (a) crude oil and refined products pipelines and terminals that serve as key infrastructure to transport onshore and offshore crude oil production to Gulf Coast and Midwest refining markets and deliver refined products from those markets to major demand centers and (b) storage tanks and financing receivables that are secured by pipelines, storage tanks, docks, truck and rail racks and other infrastructure used to stage and transport intermediate and finished products. The Partnership’s assets also include interests in entities that own natural gas and refinery gas pipelines that transport offshore natural gas to market hubs and deliver refinery gas from refineries and plants to chemical sites along the Gulf Coast.
Basis of Presentation	Basis of Presentation Our unaudited consolidated financial statements include all subsidiaries required to be consolidated under generally accepted accounting principles in the United States (“GAAP”). Our reporting currency is U.S. dollars, and all references to dollars are U.S. dollars. The accompanying unaudited consolidated financial statements and related notes have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by GAAP for complete annual financial statements. The year-end consolidated balance sheet data was derived from audited financial statements. During interim periods, we follow the accounting policies disclosed in our Annual Report on Form 10-K for the year ended December 31, 2020 (our “2020 Annual Report”), filed with the United States Securities and Exchange Commission (“SEC”) unless otherwise described herein. The unaudited consolidated financial statements for the three and six months ended June 30, 2021 and June 30, 2020 include all adjustments we believe are necessary for a fair statement of the results of operations for the interim periods presented. These adjustments are of a normal recurring nature unless otherwise disclosed. Operating results for the interim periods are not necessarily indicative of the results that may be expected for the full year. These unaudited consolidated financial statements and other information included in this Quarterly Report on Form 10-Q should be read in conjunction with our audited consolidated financial statements and notes thereto included in our 2020 Annual Report.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Standards Adopted as of January 1, 2021

Description of the Business a_3

Description of the Business and Basis of Presentation (Tables)	6 Months Ended
	Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Ownership Percentage	The following table reflects our ownership interests as of June 30, 2021: SHLX Ownership Pecten Midstream LLC (“Pecten”) 100.0 % Sand Dollar Pipeline LLC (“Sand Dollar”) 100.0 % Triton West LLC (“Triton”) 100.0 % Zydeco Pipeline Company LLC (“Zydeco”) (1) 100.0 % Mattox Pipeline Company LLC (“Mattox”) 79.0 % Amberjack Pipeline Company LLC (“Amberjack”) – Series A/Series B 75.0% / 50.0% Mars Oil Pipeline Company LLC (“Mars”) 71.5 % Odyssey Pipeline L.L.C. (“Odyssey”) 71.0 % Bengal Pipeline Company LLC (“Bengal”) 50.0 % Crestwood Permian Basin LLC (“Permian Basin”) 50.0 % LOCAP LLC (“LOCAP”) 41.48 % Explorer Pipeline Company (“Explorer”) 38.59 % Poseidon Oil Pipeline Company, L.L.C. (“Poseidon”) 36.0 % Colonial Enterprises, Inc. (“Colonial”) 16.125 % Proteus Oil Pipeline Company, LLC (“Proteus”) 10.0 % Endymion Oil Pipeline Company, LLC (“Endymion”) 10.0 % Cleopatra Gas Gathering Company, LLC (“Cleopatra”) 1.0 % (1) Prior to May 1, 2021, we owned a 92.5% ownership interest in Zydeco and SPLC owned the remaining 7.5% ownership interest. Effective May 1, 2021, SPLC transferred its 7.5% ownership interest to us as part of the May 2021 Transaction. Refer to Note 2 —Acquisitions and Other Transactions for additional information.

Acquisitions and Other Transa_2

Acquisitions and Other Transactions (Tables)	6 Months Ended
	Jun. 30, 2021
Asset Acquisition [Abstract]
Schedule Of Balances In Equity Transaction	In connection with the April 2020 Transaction, the Partnership recorded the following balances as of April 1, 2020: Equity method investment (1) $ 174 Financing receivables – related parties (2) 302 Contract assets - related parties (3) 244 April 2020 Transaction $ 720 (1) Equity method investment was recorded at SGOM’s historical carrying value of the 79% interest in Mattox. See more discussion in the section entitled “Mattox Transaction” below. (2) Financing receivables under the failed sale leaseback were recorded at the fair value of the property, plant and equipment of the Norco Assets transferred by SOPUS and Shell Chemical and recognized as a component of the Partners’ deficit. See more discussion in the section entitled “Norco Transaction” below. (3) Contract assets were recorded based on the difference between the consideration allocated to the Norco Transaction and the financing receivables. See more discussion in the section entitled “Norco Transaction” below.

Related Party Transactions (Tab

Related Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2021
Related Party Transactions [Abstract]
Schedule of Other Related Party Balances	Other related party balances consist of the following: June 30, 2021 December 31, 2020 Accounts receivable $ 33 $ 21 Prepaid expenses 7 22 Other assets 2 2 Contract assets (1) 225 233 Accounts payable (2) 14 16 Deferred revenue 18 19 Accrued liabilities (3) 19 28 Debt payable (4) 2,691 2,692 Finance lease liability 2 2 Financing receivables (1) 296 298 (1) Contract assets and Financing receivables were recognized in connection with the April 2020 Transaction. Refer to the section entitled “ Sale Leaseback ” below for additional details. Financing receivables were presented as a component of (deficit) equity. (2) Accounts payable reflects amounts owed to SPLC for reimbursement of third-party expenses incurred by SPLC for our benefit. (3) As of June 30, 2021, Accrued liabilities reflects $14 million of accrued interest and $5 million of other accrued liabilities. As of December 31, 2020, Accrued liabilities reflects $16 million of accrued interest and $12 million of other accrued liabilities. Other accrued liabilities are primarily related to the accrued operations and maintenance expenses on the Norco Assets. (4) Debt payable reflects borrowings outstanding after taking into account unamortized debt issuance costs of $3 million and $2 million as of June 30, 2021 and December 31, 2020, respectively.
Schedule of Related Party Expenses Including Personnel Costs	The following table shows related party expenses, including certain personnel costs, incurred by Shell and SPLC on our behalf that are reflected in the accompanying unaudited consolidated statements of income for the indicated periods. Included in these amounts, and disclosed below, is our share of operating and general corporate expenses, as well as the fees paid to SPLC under certain agreements. Three Months Ended June 30, Six Months Ended June 30, 2021 2020 (4) 2021 2020 (4) Allocated operating expenses $ 13 $ 16 $ 27 $ 20 Major maintenance costs (1) 2 3 3 3 Insurance expense (2) 5 5 10 10 Other (3) 14 9 21 14 Operations and maintenance – related parties $ 34 $ 33 $ 61 $ 47 Allocated general corporate expenses $ 7 $ 10 $ 12 $ 17 Management Agreement fee 3 3 5 5 Omnibus Agreement fee 2 2 5 5 General and administrative – related parties $ 12 $ 15 $ 22 $ 27 (1) Major maintenance costs are expensed as incurred in connection with the maintenance services of the Norco Assets. Refer to section entitled “ Sale Leaseback ” below for additional details. (2) The majority of our insurance coverage is provided by a wholly owned subsidiary of Shell. The remaining coverage is provided by third-party insurers. (3) Other expenses primarily relate to salaries and wages, other payroll expenses and special maintenance. (4) Certain amounts for the three and six months ended June 30, 2020 have been reclassified for consistency with current presentation. These reclassifications had no effect on the reported net income.
Schedule of Interest Income, Reduction in Financing Receivables, Cash Payments for Interest Income and Principal Repayment of Financing Receivable	The following table shows the interest income and reduction in the financing receivables for the three and six months ended June 30, 2021: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Interest income $ 7 $ 7 $ 15 $ 7 Reduction in the financing receivables 1 1 2 1 Cash payments for interest income 7 5 15 5 Cash payments on principal of the financing receivables 1 1 2 1

Equity Method Investments (Tabl

Equity Method Investments (Tables)	6 Months Ended
	Jun. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Equity Investments in Affiliates	Equity method investments comprise the following as of the dates indicated: June 30, 2021 December 31, 2020 Ownership Investment Amount Ownership Investment Amount Mattox 79.0% $ 160 79.0% $ 163 Amberjack – Series A / Series B 75.0% / 50.0% 367 75.0% / 50.0% 382 Mars 71.5% 149 71.5% 152 Bengal 50.0% 86 50.0% 88 Permian Basin 50.0% 82 50.0% 83 LOCAP 41.48% 15 41.48% 12 Explorer 38.59% 69 38.59% 73 Poseidon 36.0% — 36.0% — Colonial 16.125% 38 16.125% 29 Proteus 10.0% 13 10.0% 14 Endymion 10.0% 17 10.0% 17 $ 996 $ 1,013
Schedule of Equity Investments in Affiliates Balance Affected	Earnings from our equity method investments were as follows during the periods indicated: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 Mattox (1) $ 15 $ 15 $ 30 $ 15 Amberjack 26 29 55 58 Mars 25 28 54 59 Bengal 2 4 5 9 Explorer 26 10 33 24 Colonial 7 18 22 45 Other (2) 4 5 8 11 $ 105 $ 109 $ 207 $ 221 (1) We acquired an interest in Mattox in April 2020. The acquisition of this interest has been accounted for prospectively.
Equity Method Investments	The following tables present aggregated selected unaudited income statement data for our equity method investments on a 100% basis. However, during periods in which an acquisition occurs, the selected unaudited income statement data reflects activity from the date of the acquisition. Three Months Ended June 30, 2021 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox $ 22 $ 3 $ 19 $ 19 Amberjack 70 19 51 50 Mars 58 22 36 36 Bengal 12 8 4 4 Explorer 139 51 88 67 Colonial 306 209 97 45 Poseidon 34 9 25 24 Other (1) 53 30 23 21 (1) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Six Months Ended June 30, 2021 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox $ 44 $ 6 $ 38 $ 38 Amberjack 142 36 106 105 Mars 121 44 77 77 Bengal 25 15 10 10 Explorer 208 93 115 88 Colonial 596 342 254 142 Poseidon 76 19 57 55 Other (1) 109 62 47 44 (1) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Three Months Ended June 30, 2020 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox (1) $ 22 $ 3 $ 19 $ 19 Amberjack 74 17 57 56 Mars 61 21 40 40 Bengal 15 8 7 7 Explorer 80 43 37 28 Colonial 348 166 182 116 Poseidon 30 8 22 20 Other (2) 57 29 28 23 (1) Our interest in Mattox was acquired on April 1, 2020. (2) Included in Other is the activity associated with our investments in Permian Basin, LOCAP, Proteus and Endymion. Six Months Ended June 30, 2020 Total revenues Total operating expenses Operating income Net income Statements of Income Mattox (1) $ 22 $ 3 $ 19 $ 19 Amberjack 150 36 114 113 Mars 133 49 84 84 Bengal 32 15 17 17 Explorer 176 90 86 66 Colonial 749 329 420 285 Poseidon 63 17 46 42 Other (2) 114 56 58 48 (1) Our interest in Mattox was acquired on April 1, 2020. Mattox’s total revenues, total operating expenses and operating income (on a 100% basis) for the six months ended June 30, 2020 were $40 million, $6 million and $34 million, respectively.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 30, 2021
Property, Plant and Equipment [Abstract]
Components of Property, Plant and Equipment	Property, plant and equipment, net, consists of the following as of the dates indicated: Depreciable June 30, 2021 December 31, 2020 Land — $ 12 $ 12 Building and improvements 10 - 40 years 46 47 Pipeline and equipment (1) 10 - 30 years 1,239 1,263 Other 5 - 25 years 35 34 1,332 1,356 Accumulated depreciation and amortization (2) (666) (661) 666 695 Construction in progress 7 4 Property, plant and equipment, net $ 673 $ 699 (1) As of both June 30, 2021 and December 31, 2020, includes costs of $365 million and $372 million, respectively, related to assets under operating leases (as lessor). As of both June 30, 2021 and December 31, 2020, includes cost of $23 million related to assets under capital lease (as lessee). (2) As of June 30, 2021 and December 31, 2020, includes accumulated depreciation of $148 million and $147 million, respectively, related to assets under operating leases (as lessor). As of both June 30, 2021 and December 31, 2020, includes accumulated amortization of $9 million and $8 million, respectively, related to assets under capital lease (as lessee).

Related Party Debt (Tables)

Related Party Debt (Tables)	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Schedule of Consolidated Related Party Debt Obligations	Consolidated related party debt obligations comprise the following as of the dates indicated: June 30, 2021 December 31, 2020 Outstanding Balance Total Capacity Available Capacity Outstanding Balance Total Capacity Available Capacity 2021 Ten $ 600 $ 600 $ — $ — $ — $ — Ten 600 600 — 600 600 — Seven 600 600 — 600 600 — Five 494 760 266 494 760 266 Five 400 1,000 600 400 1,000 600 Five — — — 600 600 — 2019 Zydeco Revolver (1) — — — — 30 30 Unamortized debt issuance costs (3) n/a n/a (2) n/a n/a Debt payable – related party $ 2,691 $ 3,560 $ 866 $ 2,692 $ 3,590 $ 896 (1) The 2019 Zydeco Revolver was terminated effective June 30, 2021. See below for additional information.

(Deficit) Equity (Tables)

(Deficit) Equity (Tables)	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Schedule of Distributions Declared and/or Paid	The following table details the distributions declared and/or paid for the periods presented: Date Paid or Public SPLC SPLC General Partner Distributions to be Paid Three Months Ended Common Preferred Common IDRs 2% Total (in millions, except per unit amounts) February 14, 2020 December 31, 2019 $ 57 $ — $ 50 $ 52 $ 3 $ 162 $ 0.4600 May 15, 2020 March 31, 2020 57 — 50 52 (2) 3 (3) 162 0.4600 August 14, 2020 June 30, 2020 (1) 57 12 104 — — 173 0.4600 November 13, 2020 September 30, 2020 (1) 57 12 104 — — 173 0.4600 February 12, 2021 December 31, 2020 (1) 57 12 104 — — 173 0.4600 May 14, 2021 March 31, 2021 (1) 57 12 104 — — 173 0.4600 August 13, 2021 June 30, 2021 (4) 37 12 81 — — 130 0.3000 (1) Includes the impact of waived distributions to SPLC with respect to the April 2020 Transaction as described above. (2) This amount represents the Final IDR Payment (as defined in the Partnership Interests Restructuring Agreement) to which our general partner (or its assignee) was entitled pursuant to the Partnership Interests Restructuring Agreement. Also pursuant to the Partnership Interests Restructuring Agreement, our general partner agreed (on its own behalf and on behalf of its assignees) to waive any distributions that it would otherwise be entitled to receive with respect to the newly-issued 160 million common units that it received in the April 2020 Transaction for the quarter in which it receives the Final IDR Payment. Our general partner is not entitled to any payments with respect to the IDRs, as they were cancelled as a part of the April 2020 Transaction. (3) This amount represents the final distribution payment on the 2% economic general partner interest. Our general partner is not entitled to any payments with respect to the economic general partner interest, as it was converted into a non-economic general partner interest as a part of the April 2020 Transaction. (4) See Note 13 — Subsequent Events for additional information.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	6 Months Ended
	Jun. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table provides information about disaggregated revenue by service type and customer type: Three Months Ended June 30, Six Months Ended 2021 2020 2021 2020 Transportation services revenue – third parties $ 37 $ 25 $ 76 $ 54 Transportation services revenue – related parties (1) 51 41 95 96 Storage services revenue – third parties 2 2 4 4 Storage services revenue – related parties 2 2 4 4 Terminaling services revenue – related parties (2) 31 30 61 42 Terminaling services revenue – major maintenance service – related parties (3) 2 4 4 4 Product revenue – related parties (4) 9 2 15 9 Total Topic 606 revenue 134 106 259 213 Lease revenue – related parties 14 14 28 28 Total revenue $ 148 $ 120 $ 287 $ 241 (1) Transportation services revenue - related parties includes $1 million and $2 million, respectively, of the non-lease service component in our transportation services contracts for both the three and six months ended June 30, 2021 and 2020. (2) Terminaling services revenue - related parties is comprised of the service components in our terminaling services contracts, including the operation and maintenance service components related to the Norco Assets in connection with the April 2020 Transaction. See N ote 3 – Related Party Transactions for additional details. (3) Terminaling services revenue - major maintenance service - related parties is comprised of the service components related to providing required major maintenance to the Norco Assets in connection with the April 2020 Transaction. See N ote 3 – Related Party Transactions for additional details. (4) Product revenue is comprised of allowance oil sales.
Operating Lease, Lease Income	As of June 30, 2021, future minimum payments of both the lease and non-lease service components to be received under the ten-year contract term of these operating leases were estimated to be: Total Less than 1 year Years 2 to 3 Years 4 to 5 More than 5 years Operating leases $ 646 $ 105 $ 210 $ 210 $ 121
Contract Balances	The following table provides information about receivables and contract liabilities from contracts with customers: January 1, 2021 June 30, 2021 Receivables from contracts with customers – third parties $ 19 $ 11 Receivables from contracts with customers – related parties 18 25 Contract assets – related parties 233 225 Deferred revenue – third parties 4 — Deferred revenue – related parties (1) 19 18
Contract with Customer, Estimated Future Amortization	The estimated future amortization related to the contract assets for the next five years is as follows: Remainder of 2021 2022 2023 2024 2025 2026 Amortization $ 8 $ 16 $ 16 $ 17 $ 17 $ 15
Contract with Customer, Deferred Revenue Activity	Significant changes in the deferred revenue balances with customers during the period are as follows: December 31, 2020 Additions (1) Reductions (2) June 30, 2021 Deferred revenue – third parties $ 4 $ 2 $ (6) $ — Deferred revenue – related parties 19 10 (11) 18 (1) Deferred revenue additions resulted from $6 million deficiency payments from minimum volume commitment contracts and $6 million of deferred revenue related to the major maintenance service components of our terminaling service contracts on the Norco Assets. (2) Deferred revenue reductions resulted from revenue earned through the actual or estimated use and expiration of deficiency credits.
Remaining Performance Obligations	The following table includes revenue expected to be recognized in the future related to performance obligations exceeding one year of their initial terms that are unsatisfied or partially unsatisfied as of June 30, 2021: Total Remainder of 2021 2022 2023 2024 2025 and beyond Revenue expected to be recognized on multi-year committed shipper transportation contracts $ 442 $ 32 $ 63 $ 63 $ 57 $ 227 Revenue expected to be recognized on other multi-year transportation service contracts (1) 32 3 6 6 4 13 Revenue expected to be recognized on multi-year storage service contracts 23 5 10 4 4 — Revenue expected to be recognized on multi-year terminaling service contracts (1) 286 22 45 45 45 129 Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts (2) 1,464 53 106 106 107 1,092 $ 2,247 $ 115 $ 230 $ 224 $ 217 $ 1,461 (1) Relates to the non-lease service components of certain of our long-term transportation and terminaling service contracts, which are accounted for as operating leases. (2) Relates to the operation and maintenance service components and the major maintenance service components of our terminaling service contracts on the Norco Assets in connection with the April 2020 Transaction.

Net Income Per Limited Partne_2

Net Income Per Limited Partner Unit (Tables)	6 Months Ended
	Jun. 30, 2021
Partners' Capital Notes [Abstract]
Schedule of Allocation of Net Income Attributable to the Partnership to Arrive at Net Income Per Limited Partner Unit	The following tables show the allocation of net income attributable to the Partnership to arrive at net income per limited partner unit: Three Months Ended June 30, Six Months Ended 2021 (1) 2020 (1) 2021 (1) 2020 Net income * * * $ 286 Less: Net income attributable to noncontrolling interests * * * 7 Net income attributable to the Partnership * * * 279 Less: General partner’s distribution declared * * * 55 Preferred unitholder’s interest in net income * * * 12 Limited partners’ distribution declared on common units * * * 268 Distributions in excess of income * * * $ (56) (1) Effective April 1, 2020, the classes of participating securities included only common units, as the general partner units and the IDRs were eliminated and the Series A Preferred Units are not considered a participating security. Therefore, the allocation of net income attributable to the Partnership to arrive at net income per limited partner unit is not applicable for the three and six months ended June 30, 2021, nor to the three months ended June 30, 2020.
Schedule of Basic and Diluted Net Income Per Unit	Three Months Ended June 30, 2021 Six Months Ended June 30, 2021 Limited Partners’ Common Units (in millions of dollars, except per unit data) Net income attributable to the Partnership’s common unitholders (basic) $ 150 $ 301 Dilutive effect of preferred units 12 24 Net income attributable to the Partnership’s common unitholders (diluted) $ 162 $ 325 Weighted average units outstanding - Basic 393.3 393.3 Dilutive effect of preferred units 50.8 50.8 Weighted average units outstanding - Diluted 444.1 444.1 Net income per limited partner unit: Basic $ 0.38 $ 0.76 Diluted $ 0.36 $ 0.73 Three Months Ended June 30, 2020 Limited Partners’ Common Units (in millions of dollars, except per unit data) Net income attributable to the Partnership’s common unitholders (basic) $ 129 Dilutive effect of preferred units 12 Net income attributable to the Partnership’s common unitholders (diluted) $ 141 Weighted average units outstanding - Basic 393.3 Dilutive effect of preferred units 50.8 Weighted average units outstanding - Diluted 444.1 Net income per limited partner unit: Basic $ 0.33 Diluted $ 0.32 Six Months Ended June 30, 2020 General Partner Limited Partners’ Common Units Total (in millions of dollars, except per unit data) Distributions declared $ 55 $ 268 $ 323 Distributions in excess of income — (56) (56) Net income attributable to the Partnership's common unitholders (basic) $ 55 $ 212 $ 267 Dilutive effect of preferred units 12 Net income attributable to the Partnership's common unitholders (dilutive) $ 224 Weighted average units outstanding - Basic 313.3 Dilutive effect of preferred units 25.4 Weighted average units outstanding - Diluted 338.7 Net income per limited partner unit: Basic $ 0.68 Diluted $ 0.66

Description of the Business a_4

Description of the Business and Basis of Presentation (Details)	6 Months Ended
	Jun. 30, 2021segmentshares	May 01, 2021	Apr. 30, 2021	Dec. 31, 2020shares	Apr. 01, 2020shares
Description Of Business And Basis Of Presentation [Line Items]
Common units (in units)					393,289,537
Number of reportable segments | segment	1
Shell Pipeline Company L P
Description Of Business And Basis Of Presentation [Line Items]
Preferred units (in units)	50,782,904			50,782,904
Limited Partner | Partnership Interests Restructuring Agreement | Series A Perpetual Convertible Preferred Units
Description Of Business And Basis Of Presentation [Line Items]
Preferred units (in units)	50,782,904
Economic Interest | General Partner SPLC
Description Of Business And Basis Of Presentation [Line Items]
Noncontrolling interest					2.00%
Shell Pipeline Company L P | Limited Partner
Description Of Business And Basis Of Presentation [Line Items]
Ownership interest percentage	68.50%
Common units (in units)	269,457,304
Shell Pipeline Company L P | Limited Partner | Common Units And Series A Perpetual Convertible Preferred Units
Description Of Business And Basis Of Presentation [Line Items]
Ownership interest percentage	72.00%
Pecten Midstream LLC (“Pecten”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	100.00%
Sand Dollar Pipeline LLC (“Sand Dollar”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	100.00%
Triton West LLC (“Triton”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	100.00%
Zydeco Pipeline Company LLC (“Zydeco”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership		100.00%
Zydeco Pipeline Company LLC (“Zydeco”) | Zydeco Pipeline Company LLC (“Zydeco”)
Description Of Business And Basis Of Presentation [Line Items]
Retained Ownership			92.50%
Zydeco Pipeline Company LLC (“Zydeco”) | Zydeco Pipeline Company LLC (“Zydeco”) | Shell Pipeline Company L P
Description Of Business And Basis Of Presentation [Line Items]
Retained Ownership			7.50%
Ownership percentage transferred		7.50%
Mattox Pipeline Company LLC ("Mattox")
Description Of Business And Basis Of Presentation [Line Items]
Ownership	79.00%
Amberjack Pipeline Company LLC (“Amberjack”) - Series A
Description Of Business And Basis Of Presentation [Line Items]
Ownership	75.00%			75.00%
Amberjack Pipeline Company LLC (“Amberjack”) - Series B
Description Of Business And Basis Of Presentation [Line Items]
Ownership	50.00%			50.00%
Mars Oil Pipeline Company LLC (“Mars”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	71.50%			71.50%
Odyssey Pipeline L.L.C. (“Odyssey”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	71.00%
Bengal Pipeline Company LLC (“Bengal”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	50.00%			50.00%
Crestwood Permian Basin LLC (“Permian Basin”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	50.00%			50.00%
LOCAP LLC (“LOCAP”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	41.48%			41.48%
Explorer Pipeline Company ("Explorer")
Description Of Business And Basis Of Presentation [Line Items]
Ownership	38.59%			38.59%
Poseidon Oil Pipeline Company LLC (“Poseidon”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	36.00%			36.00%
Colonial Pipeline Company (“Colonial”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	16.125%			16.125%
Proteus Oil Pipeline Company, LLC (“Proteus”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	10.00%			10.00%
Endymion Oil Pipeline Company, LLC (“Endymion”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	10.00%			10.00%
Cleopatra Gas Gathering Company, LLC (“Cleopatra”)
Description Of Business And Basis Of Presentation [Line Items]
Ownership	1.00%

Acquisitions and Other Transa_3

Acquisitions and Other Transactions - May 2021 Transactions (Details) - USD ($) $ in Millions	May 01, 2021	Apr. 29, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Asset Acquisition [Line Items]
Payments to acquire assets						$ 4	$ 9
Impairment of fixed assets			$ 0		$ 0	$ 3	$ 0
Auger Pipeline
Asset Acquisition [Line Items]
Impairment of fixed assets				$ 3
Cash consideration received		$ 2
Zydeco Pipeline Company LLC (“Zydeco”)
Asset Acquisition [Line Items]
Ownership	100.00%
Zydeco Pipeline Company LLC (“Zydeco”) | Zydeco Pipeline Company LLC (“Zydeco”) | Shell Pipeline Company L P
Asset Acquisition [Line Items]
Ownership percentage transferred	7.50%
Zydeco Pipeline Company LLC (“Zydeco”) | Zydeco Pipeline Company LLC (“Zydeco”) | Shell Pipeline Company L P | Triton West LLC (“Triton”)
Asset Acquisition [Line Items]
Payments to acquire assets	$ 10
Ownership percentage transferred	7.50%

Acquisitions and Other Transa_4

Acquisitions and Other Transactions - April 2020 Transaction (Details) $ / shares in Units, $ in Millions	Apr. 01, 2020USD ($)quarter$ / sharesshares	Jun. 30, 2021USD ($)$ / sharesshares	Mar. 31, 2021$ / shares	Dec. 31, 2020USD ($)$ / shares	Sep. 30, 2020$ / shares	Jun. 30, 2020USD ($)$ / shares	Mar. 31, 2020$ / shares	Dec. 31, 2019$ / shares	Jun. 30, 2021USD ($)$ / sharesshares	Jun. 30, 2020$ / shares	Apr. 30, 2020quarter
Asset Acquisition [Line Items]
Equity method investments		$ 996		$ 1,013					$ 996
Financing receivables – related parties		296		298					296
Equity Method Investments And Other Assets	$ 720
Partners' capital		$ (469)		$ (481)					$ (469)
April 2020 Transaction						$ 416
Common units (in units) | shares	393,289,537
Distributions paid per limited partner unit (in dollars per share) | $ / shares		$ 0.3000	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.7600	$ 0.9200
Affiliated Entity | Norco Transaction | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	11.00%
Affiliated Entity | Mattox Transaction | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	14.00%
Affiliated Entity | GP/IDR Restructuring | Valuation Technique, Discounted Cash Flow
Asset Acquisition [Line Items]
Measurement input	20.00%
Mattox Pipeline Company LLC ("Mattox")
Asset Acquisition [Line Items]
Equity method investments	$ 174
April 2020 Transaction | Norco Transaction
Asset Acquisition [Line Items]
Financing receivables – related parties	302
April 2020 Transaction | Affiliated Entity | Norco Transaction
Asset Acquisition [Line Items]
Contract asset - related parties	244
Consideration allocated, fair value	$ 546
April 2020 Transaction | Terminaling Services | Affiliated Entity | Norco Transaction
Asset Acquisition [Line Items]
Annual payments receivable		$ 140							$ 140
Annual payments receivable, gross		151							151
Annual payments receivable, net		$ 11							$ 11
Preferred Units
Asset Acquisition [Line Items]
Distributions paid per limited partner unit (in dollars per share) | $ / shares	$ 0.2363	$ 0.2363							$ 0.4726
General Partner SPLC | Shell Pipeline Company L P
Asset Acquisition [Line Items]
April 2020 Transaction						$ 4,069
Purchase And Sale Agreement | Mattox Pipeline Company LLC ("Mattox")
Asset Acquisition [Line Items]
Equity method investment, ownership interest acquired	79.00%
Partnership Interests Restructuring Agreement | General Partner SPLC
Asset Acquisition [Line Items]
Distributions payable, amount waved	$ 20
Distribution payable, number of consecutive quarters | quarter	4										4
Partnership Interests Restructuring Agreement | Limited Partner | Series A Perpetual Convertible Preferred Units
Asset Acquisition [Line Items]
Unit distribution (in units) | shares	50,782,904
Unit distribution (in dollars per unit) | $ / shares	$ 23.63
Partnership Interests Restructuring Agreement | Limited Partner | Common Units
Asset Acquisition [Line Items]
Unit distribution (in units) | shares	160,000,000
Economic Interest | General Partner SPLC
Asset Acquisition [Line Items]
Noncontrolling interest	2.00%
Shell Pipeline Company L P | Limited Partner
Asset Acquisition [Line Items]
Common units (in units) | shares		269,457,304							269,457,304
Mattox Pipeline Company LLC ("Mattox")
Asset Acquisition [Line Items]
Ownership		79.00%							79.00%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) $ in Millions	Feb. 01, 2019	Nov. 03, 2014USD ($)	Apr. 30, 2020USD ($)quarter	Jun. 30, 2021USD ($)facility	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)facility	Jun. 30, 2020USD ($)	Dec. 31, 2020	Apr. 01, 2020quarter
Related Party Transaction [Line Items]
Health and life insurance costs				$ 1	$ 1	$ 3	$ 3
Defined contribution benefit plan costs				$ 1	1	$ 1	1
Severance expenses					$ 5		$ 5
Purchase And Sale Agreement | Mattox Pipeline Company LLC ("Mattox")
Related Party Transaction [Line Items]
Equity method investment, ownership interest acquired									79.00%
Partnership Interests Restructuring Agreement | General Partner SPLC
Related Party Transaction [Line Items]
Distribution to holders of incentive distribution rights waived			$ 20
Distribution payable, number of consecutive quarters | quarter			4						4
Trade Marks License Agreement
Related Party Transaction [Line Items]
Trademarks agreement, termination notice period	360 days
Shell Treasury Center West Inc
Related Party Transaction [Line Items]
Number of revolving credit facilities | facility				5		5
Five Year Fixed Facility | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Five Year Fixed Facility | Shell Treasury Center West Inc | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Ten Year Fixed Facility | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						10 years
Ten Year Fixed Facility | Shell Treasury Center West Inc | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						10 years
Seven Year Fixed Facility | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						7 years
Seven Year Fixed Facility | Shell Treasury Center West Inc | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						7 years
Five Year Revolver due July 2023 | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Five Year Revolver due July 2023 | Shell Treasury Center West Inc | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Five Year Revolver due December 2022 | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Five Year Revolver due December 2022 | Shell Treasury Center West Inc | Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Shell Pipeline Company L P | Omnibus Agreement
Related Party Transaction [Line Items]
Payment of general and administrative fee		$ 10
Odyssey Pipeline L.L.C. (“Odyssey”) | GEL Offshore Pipeline LLC
Related Party Transaction [Line Items]
Noncontrolling interest				29.00%		29.00%		29.00%
Zydeco Pipeline Company LLC (“Zydeco”) | Shell Pipeline Company L P
Related Party Transaction [Line Items]
Noncontrolling interest								7.50%

Related Party Transactions - Sc

Related Party Transactions - Schedule of Other Related Party Balances (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Accounts receivable	$ 33	$ 21
Prepaid expenses	7	22
Other assets	2	2
Contract assets	225	233
Accounts payable	14	16
Deferred revenue	18	19
Accrued liabilities	19	28
Debt payable	2,691	2,692
Finance lease liability	2	2
Financing receivables	296	298
Accrued interest, related parties	14	16
Other accrued liabilities, related parties	5	12
Unamortized debt issuance costs	3	2
Affiliated Entity
Related Party Transaction [Line Items]
Unamortized debt issuance costs	$ 3	$ 2

Related Party Transactions - _2

Related Party Transactions - Schedule of Condensed Combined Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2017
Related Party Transactions [Abstract]
Allocated operating expenses	$ 13	$ 16	$ 27	$ 20
Maintenance service costs	2	3	3	3
Insurance expense	5	5	10	10
Other	14	9	21	14
Operations and maintenance – related parties	34	33	61	47	$ 47
Allocated general corporate expenses	7	10	12	17
Management Agreement fee	3	3	5	5
Omnibus Agreement fee	2	2	5	5
General and administrative – related parties	$ 12	$ 15	$ 22	$ 27

Related Party Transactions - Sa

Related Party Transactions - Sale Leaseback (Details) - April 2020 Transaction - Terminaling Services - Affiliated Entity - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Related Party Transaction [Line Items]
Interest income	$ 7	$ 7	$ 15	$ 7
Reduction in the financing receivables	1	1	2	1
Proceeds from interest income	7	5	15	5
Proceeds from principal repayments	1	$ 1	2	$ 1
Norco Transaction
Related Party Transaction [Line Items]
Annual payments receivable	140		140
Annual payments receivable, gross	151		151
Annual payments receivable, net	$ 11		$ 11
Shell Oil Products (SOPUS)
Related Party Transaction [Line Items]
Financing receivable, imputed interest rate			11.10%
Shell Chemical
Related Party Transaction [Line Items]
Financing receivable, imputed interest rate			7.40%

Equity Method Investments - Sch

Equity Method Investments - Schedule of Equity Investments in Affiliates (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Investment Amount	$ 996,000,000	$ 1,013,000,000
Mattox
Schedule of Equity Method Investments [Line Items]
Ownership	79.00%	79.00%
Investment Amount	$ 160,000,000	$ 163,000,000
Amberjack – Series A / Series B
Schedule of Equity Method Investments [Line Items]
Investment Amount	$ 367,000,000	$ 382,000,000
Amberjack Pipeline Company LLC (“Amberjack”) - Series A
Schedule of Equity Method Investments [Line Items]
Ownership	75.00%	75.00%
Amberjack Pipeline Company LLC (“Amberjack”) - Series B
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Mars
Schedule of Equity Method Investments [Line Items]
Ownership	71.50%	71.50%
Investment Amount	$ 149,000,000	$ 152,000,000
Bengal
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Investment Amount	$ 86,000,000	$ 88,000,000
Crestwood Permian Basin LLC (“Permian Basin”)
Schedule of Equity Method Investments [Line Items]
Ownership	50.00%	50.00%
Investment Amount	$ 82,000,000	$ 83,000,000
LOCAP
Schedule of Equity Method Investments [Line Items]
Ownership	41.48%	41.48%
Investment Amount	$ 15,000,000	$ 12,000,000
Explorer
Schedule of Equity Method Investments [Line Items]
Ownership	38.59%	38.59%
Investment Amount	$ 69,000,000	$ 73,000,000
Poseidon
Schedule of Equity Method Investments [Line Items]
Ownership	36.00%	36.00%
Investment Amount	$ 0	$ 0	$ 0
Colonial Pipeline Company (“Colonial”)
Schedule of Equity Method Investments [Line Items]
Ownership	16.125%	16.125%
Investment Amount	$ 38,000,000	$ 29,000,000
Proteus
Schedule of Equity Method Investments [Line Items]
Ownership	10.00%	10.00%
Investment Amount	$ 13,000,000	$ 14,000,000
Endymion
Schedule of Equity Method Investments [Line Items]
Ownership	10.00%	10.00%
Investment Amount	$ 17,000,000	$ 17,000,000

Equity Method Investments - Add

Equity Method Investments - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Distribution from equity method investment	$ 128,000,000	$ 135,000,000	$ 251,000,000	$ 270,000,000
Unamortized basis differences included in equity investments	80,000,000		80,000,000		$ 84,000,000
Amortization expense (income)	2,000,000	2,000,000	4,000,000	4,000,000
Equity method investments	996,000,000		996,000,000		1,013,000,000
Impairment charges	3,000,000
Poseidon
Schedule of Equity Method Investments [Line Items]
Equity method investments	0		0		0	$ 0
Investment, excess distribution	10,000,000	9,000,000	24,000,000	18,000,000
Crestwood Permian Basin LLC (“Permian Basin”)
Schedule of Equity Method Investments [Line Items]
Equity method investments	82,000,000		82,000,000		83,000,000
Capital contribution	1,000,000	$ 0	3,000,000	$ 0
Amberjack
Schedule of Equity Method Investments [Line Items]
Equity method investments	367,000,000		$ 367,000,000		$ 382,000,000
Impairment charges	$ 4,000,000

Equity Method Investments - Sum

Equity Method Investments - Summary of Income Statement Data for Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	$ 105		$ 109		$ 207	$ 221
Total revenue	148		120		287	241
Costs and Expenses	83		79		158	155
Operating Income (Loss)	65		41		129	86
Net income	166	$ 167	144	$ 142	333	286
Mattox
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	15		15		30	15
Mattox | April 2020 Acquisition
Schedule of Equity Method Investments [Line Items]
Total revenue						40
Costs and Expenses						6
Operating Income (Loss)						34
Mattox | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	22		22		44	22
Costs and Expenses	3		3		6	3
Operating Income (Loss)	19		19		38	19
Net income	19		19		38	19
Amberjack
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	26		29		55	58
Amberjack | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	70		74		142	150
Costs and Expenses	19		17		36	36
Operating Income (Loss)	51		57		106	114
Net income	50		56		105	113
Mars
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	25		28		54	59
Mars | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	58		61		121	133
Costs and Expenses	22		21		44	49
Operating Income (Loss)	36		40		77	84
Net income	36		40		77	84
Bengal
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	2		4		5	9
Bengal | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	12		15		25	32
Costs and Expenses	8		8		15	15
Operating Income (Loss)	4		7		10	17
Net income	4		7		10	17
Explorer
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	26		10		33	24
Explorer | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	139		80		208	176
Costs and Expenses	51		43		93	90
Operating Income (Loss)	88		37		115	86
Net income	67		28		88	66
Colonial Pipeline Company (“Colonial”)
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	7		18		22	45
Colonial Pipeline Company (“Colonial”) | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	306		348		596	749
Costs and Expenses	209		166		342	329
Operating Income (Loss)	97		182		254	420
Net income	45		116		142	285
Poseidon | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	34		30		76	63
Costs and Expenses	9		8		19	17
Operating Income (Loss)	25		22		57	46
Net income	24		20		55	42
Other
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	4		5		8	11
Other | Equity Method Investment, Nonconsolidated Investee, Other
Schedule of Equity Method Investments [Line Items]
Total revenue	53		57		109	114
Costs and Expenses	30		29		62	56
Operating Income (Loss)	23		28		47	58
Net income	$ 21		$ 23		$ 44	$ 48

Property, Plant and Equipment -

Property, Plant and Equipment - Components of Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Land	$ 12			$ 12		$ 12
Building and improvements	46			46		47
Pipeline and equipment	1,239			1,239		1,263
Other	35			35		34
Property, plant and equipment, gross	1,332			1,332		1,356
Accumulated depreciation and amortization	(666)			(666)		(661)
Property plant and equipment excluding construction in progress	666			666		695
Construction in progress	7			7		4
Property, plant and equipment, net	673			673		699
Operating lease, accumulated depreciation	148			148		147
Finance lease, accumulated depreciation	9			9		8
Depreciation and amortization expense	12		$ 13	25	$ 26
Impairment of fixed assets	$ 0		$ 0	$ 3	$ 0
Auger Pipeline
Property Plant And Equipment [Line Items]
Impairment of fixed assets		$ 3
Building and Improvements | Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				10 years
Building and Improvements | Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				40 years
Pipeline and Equipment
Property Plant And Equipment [Line Items]
Operating lease cost				$ 365		372
Finance lease cost				$ 23		$ 23
Pipeline and Equipment | Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				10 years
Pipeline and Equipment | Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				30 years
Other | Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				5 years
Other | Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, depreciable life				25 years

Related Party Debt - Schedule o

Related Party Debt - Schedule of Consolidated Related Party Debt Obligations (Details) - USD ($)	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Line Of Credit Facility [Line Items]
Outstanding Balance	$ 2,691,000,000	$ 2,692,000,000
Unamortized debt issuance costs	(3,000,000)	(2,000,000)
Total Capacity	3,560,000,000	3,590,000,000
Available Capacity	$ 866,000,000	896,000,000
Revolving Credit Facility | 2021 Ten Year Fixed Facility
Line Of Credit Facility [Line Items]
Debt instrument term	10 years
Outstanding Balance	$ 600,000,000	0
Total Capacity	600,000,000	0
Available Capacity	$ 0	0
Revolving Credit Facility | Ten Year Fixed Facility
Line Of Credit Facility [Line Items]
Debt instrument term	10 years
Outstanding Balance	$ 600,000,000	600,000,000
Total Capacity	600,000,000	600,000,000
Available Capacity	$ 0	0
Revolving Credit Facility | Seven Year Fixed Facility
Line Of Credit Facility [Line Items]
Debt instrument term	7 years
Outstanding Balance	$ 600,000,000	600,000,000
Total Capacity	600,000,000	600,000,000
Available Capacity	$ 0	0
Revolving Credit Facility | Five Year Revolver due July 2023
Line Of Credit Facility [Line Items]
Debt instrument term	5 years
Outstanding Balance	$ 494,000,000	494,000,000
Total Capacity	760,000,000	760,000,000
Available Capacity	266,000,000	266,000,000
Revolving Credit Facility | Five Year Revolver due December 2022
Line Of Credit Facility [Line Items]
Outstanding Balance	400,000,000	400,000,000
Total Capacity	1,000,000,000	1,000,000,000
Available Capacity	$ 600,000,000	600,000,000
Revolving Credit Facility | Five Year Fixed Facility
Line Of Credit Facility [Line Items]
Debt instrument term	5 years
Outstanding Balance	$ 0	600,000,000
Total Capacity	0	600,000,000
Available Capacity	0	0
Revolving Credit Facility | Zydeco Revolver
Line Of Credit Facility [Line Items]
Outstanding Balance	0	0
Total Capacity	0	30,000,000
Available Capacity	$ 0	$ 30,000,000

Related Party Debt - Additional

Related Party Debt - Additional Information (Details) - USD ($)	Mar. 23, 2021	Mar. 16, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Line Of Credit Facility [Line Items]
Interest and fee expenses			$ 20,000,000	$ 23,000,000	$ 41,000,000	$ 47,000,000
Interest paid			17,000,000	$ 24,000,000	41,000,000	$ 49,000,000
Borrowing capacity			3,560,000,000		3,560,000,000		$ 3,590,000,000
Long-term debt, carrying value			2,694,000,000		2,694,000,000		2,694,000,000
Long-term debt, fair value			2,898,000,000		2,898,000,000		2,928,000,000
2021 Ten Year Fixed Facility | Revolving Credit Facility
Line Of Credit Facility [Line Items]
Borrowing capacity			600,000,000		$ 600,000,000		0
Debt instrument term					10 years
2021 Ten Year Fixed Facility | Revolving Credit Facility | Shell Treasury Center West Inc
Line Of Credit Facility [Line Items]
Borrowing capacity		$ 600,000,000
Debt instrument term		10 years
Debt instrument, interest rate		2.96%
Debt issuance costs		$ 0
Five Year Fixed Facility | Revolving Credit Facility
Line Of Credit Facility [Line Items]
Borrowing capacity			$ 0		$ 0		$ 600,000,000
Debt instrument term					5 years
Five Year Fixed Facility | Revolving Credit Facility | Shell Treasury Center West Inc
Line Of Credit Facility [Line Items]
Debt instrument term					5 years
Early prepayment fee	$ 2,000,000

(Deficit) Equity (Details)

(Deficit) Equity (Details) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020	Apr. 01, 2020	Mar. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Partners' capital	$ (467,000,000)	$ (379,000,000)	$ (467,000,000)	$ (458,000,000)		$ (774,000,000)	$ (749,000,000)
Issuance of common units, maximum proceeds	$ 300,000,000
General Partner SPLC
Class of Stock [Line Items]
Capital units, publicly owned (in shares)					4,761,012
Common Units
Class of Stock [Line Items]
Units issued under the ATM Program (in shares)	1,000,000,000
Shell Pipeline Company L P | General Partner SPLC
Class of Stock [Line Items]
Partners' capital		$ 0			$ (4,000,000,000)	$ (4,014,000,000)	$ (4,014,000,000)
Shell Pipeline Company L P | General Partner SPLC | General Partner Interest
Class of Stock [Line Items]
Aggregate percentage of general partner interest		2.00%
Shell Pipeline Company L P | Limited Partner | Limited Partner Interest
Class of Stock [Line Items]
Aggregate percentage of general partner interest		98.00%
Shell Pipeline Company L P | Common Units
Class of Stock [Line Items]
Capital units, publicly owned (in shares)	269,457,304

(Deficit) Equity - Units Outsta

(Deficit) Equity - Units Outstanding (Details)	Apr. 01, 2020$ / sharesshares	Jun. 30, 2021shares	Dec. 31, 2020shares
Class of Stock [Line Items]
Common unitholders' capital account, units outstanding (in shares)		393,289,537	393,289,537
Percent of consideration payable in cash	90.00%
Common Units
Class of Stock [Line Items]
Common unitholders' capital account, units outstanding (in shares)		123,832,233	123,832,233
Limited Partner | Partnership Interests Restructuring Agreement | Series A Perpetual Convertible Preferred Units
Class of Stock [Line Items]
Preferred units, issued (in shares)	50,782,904
Unit distribution (in dollars per unit) | $ / shares	$ 23.63
Preferred Partner
Class of Stock [Line Items]
Capital units, publicly owned (in shares)		50,782,904	50,782,904
Preferred Partner | Series A Perpetual Convertible Preferred Units
Class of Stock [Line Items]
Conversion ratio	1
General Public | Common Units
Class of Stock [Line Items]
Capital units, publicly owned (in shares)		123,832,233
Shell Pipeline Company L P
Class of Stock [Line Items]
Preferred units, issued (in shares)		50,782,904	50,782,904
Shell Pipeline Company L P | Series A Perpetual Convertible Preferred Units
Class of Stock [Line Items]
Conversion ratio	1
Closing price per share, threshold (in dollars per share) | $ / shares	$ 33.082
Closing price per share, percent of issuance price, threshold	140.00%
Closing price per share, number of trading days threshold	20 days
Closing price per share, number of trading days preceding notice of conversion	30 days
Shell Pipeline Company L P | Common Units
Class of Stock [Line Items]
Common unitholders' capital account, units outstanding (in shares)		269,457,304	269,457,304
Capital units, publicly owned (in shares)		269,457,304
Shell Pipeline Company L P | Limited Partner | Limited Partner Interest
Class of Stock [Line Items]
Ownership interest percentage		68.50%

(Deficit) Equity - Schedule of

(Deficit) Equity - Schedule of Distributions Declared and/or Paid (Details) - USD ($) $ / shares in Units, $ in Millions	Apr. 01, 2020	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2018
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		$ 130	$ 173	$ 173	$ 173	$ 173	$ 162	$ 162
Distributions paid per limited partner unit (in dollars per share)		$ 0.3000	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.7600	$ 0.9200
Dilutive effect of preferred units		$ 12				$ 12
Preferred Units
Distribution Made To Limited Partner [Line Items]
Distributions paid per limited partner unit (in dollars per share)	$ 0.2363	$ 0.2363							$ 0.4726
Shell Midstream Partners L.P.
Distribution Made To Limited Partner [Line Items]
Aggregate percentage of general partner interest			2.00%								2.00%
Zydeco Pipeline Company LLC (“Zydeco”)
Distribution Made To Limited Partner [Line Items]
Distributions to noncontrolling interest		$ 0				2			$ 1	$ 3
Odyssey Pipeline L.L.C. (“Odyssey”)
Distribution Made To Limited Partner [Line Items]
Distributions to noncontrolling interest		3				2			$ 7	$ 6
Common Units | General Public
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		37	$ 57	$ 57	$ 57	57	$ 57	$ 57
Common Units | Shell Pipeline Company L P
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		81	104	104	104	104	50	50
Preferred Units | Shell Pipeline Company L P
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		12	12	12	12	12	0	0
General Partner SPLC
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		0	0	0	0	0	3	3
General Partner SPLC | Partnership Interests Restructuring Agreement
Distribution Made To Limited Partner [Line Items]
Distributions payable, amount waved	$ 20
General Partner SPLC | IDR's
Distribution Made To Limited Partner [Line Items]
Distributions declared and/or paid		$ 0	$ 0	$ 0	$ 0	$ 0	$ 52	$ 52
Limited Partner | Partnership Interests Restructuring Agreement | Common Units
Distribution Made To Limited Partner [Line Items]
Unit distribution (in units)	160,000,000

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregated Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	$ 134	$ 106	$ 259	$ 213
Lease revenue – related parties	14	14	28	28
Total revenue	148	120	287	241
Related Parties
Disaggregation of Revenue [Line Items]
Lease revenue – related parties	14	14	28	28
Transportation Services | Third Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	37	25	76	54
Transportation Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	51	41	95	96
Storage Services | Third Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	2	4	4
Storage Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	2	4	4
Terminaling Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	31	30	61	42
Terminaling Services, Major Maintenance | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	4	4	4
Product Revenue | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	9	2	15	9
Transportation Services Nonlease Service | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	$ 1	$ 1	$ 2	$ 2

Revenue Recognition - Receivabl

Revenue Recognition - Receivables and Contract Liabilities (Details) $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)term
Disaggregation of Revenue [Line Items]
Total	$ 646
Less than 1 year	105
Years 2 to 3	210
Years 4 to 5	210
More than 5 years	$ 121
Transportation Services Operating Leases, Five Year Terms
Disaggregation of Revenue [Line Items]
Initial term	10 years
Number of additional terms | term	2
Additional term	5 years
Transportation Services Operating Leases, One Year Terms
Disaggregation of Revenue [Line Items]
Number of additional terms | term	10
Additional term	1 year
Transportation Services Operating Leases
Disaggregation of Revenue [Line Items]
Initial term	10 years
Transportation Services Operating Leases Amended
Disaggregation of Revenue [Line Items]
Additional term	14 months

Revenue Recognition - Terminali

Revenue Recognition - Terminaling Service (Details) - Terminaling Services $ in Millions	6 Months Ended
	Jun. 30, 2021USD ($)
Disaggregation of Revenue [Line Items]
Agreement term	15 years
Agreement term extension	5 years
April 2020 Transaction | Norco Transaction | Affiliated Entity
Disaggregation of Revenue [Line Items]
Annual payments receivable	$ 140
Annual payments receivable, gross	151
Annual payments receivable, net	$ 11

Revenue Recognition - Contract

Revenue Recognition - Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Jan. 01, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable – third parties, net	$ 13		$ 13			$ 20
Contract assets – related parties	225		225			233
Deferred revenue – third parties	0		0			4
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, beginning balance			4
Deferred revenue, ending balance	0		0
Contract With Customer, Estimated Future Amortization [Abstract]
Remainder of 2021	8		8
2022	16		16
2023	16		16
2024	17		17
2025	17		17
2026	15		15
Minimum Volume Commitment
Movement in Deferred Revenue [Roll Forward]
Additions			$ 6
Terminaling Services
Disaggregation of Revenue [Line Items]
Agreement term			15 years
Capitalized contract cost, amortization	4	$ 4	$ 8	$ 4
Movement in Deferred Revenue [Roll Forward]
Additions			6
Third Parties
Disaggregation of Revenue [Line Items]
Accounts receivable – third parties, net	11		11		$ 19
Deferred revenue – third parties	0		0		4	4
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, beginning balance			4
Additions			2
Reductions			(6)
Deferred revenue, ending balance	0		0
Related Parties
Disaggregation of Revenue [Line Items]
Accounts receivable – third parties, net	25		25		18
Contract assets – related parties	225		225		233
Deferred revenue – third parties	18		18		$ 19	$ 19
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, beginning balance			19
Additions			10
Reductions			(11)
Deferred revenue, ending balance	$ 18		$ 18

Revenue Recognition - Remaining

Revenue Recognition - Remaining Performance Obligations (Details) $ in Millions	Jun. 30, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 2,247
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 115
Revenue, remaining performance obligation, expected timing of satisfaction, period	6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 230
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 224
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 217
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 1,461
Revenue, remaining performance obligation, expected timing of satisfaction, period
Revenue expected to be recognized on multi-year committed shipper transportation contracts
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 442
Revenue expected to be recognized on multi-year committed shipper transportation contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	32
Revenue expected to be recognized on multi-year committed shipper transportation contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	63
Revenue expected to be recognized on multi-year committed shipper transportation contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	63
Revenue expected to be recognized on multi-year committed shipper transportation contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	57
Revenue expected to be recognized on multi-year committed shipper transportation contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	227
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	32
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	3
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	6
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	6
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	4
Revenue expected to be recognized on other multi-year transportation service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	13
Revenue expected to be recognized on multi-year storage service contracts
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	23
Revenue expected to be recognized on multi-year storage service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	5
Revenue expected to be recognized on multi-year storage service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	10
Revenue expected to be recognized on multi-year storage service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	4
Revenue expected to be recognized on multi-year storage service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	4
Revenue expected to be recognized on multi-year storage service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	0
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	286
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	22
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	45
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	45
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	45
Revenue expected to be recognized on multi-year terminaling service contracts in place as of September 30, 2019 | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	129
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	1,464
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	53
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	106
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	106
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	107
Revenue expected to be recognized on multi-year operation and major maintenance terminaling service contracts | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 1,092

Net Income Per Limited Partne_3

Net Income Per Limited Partner Unit - Schedule of Allocation of Net Income to Arrive at Net Income Per Limited Partner Unit (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Apr. 01, 2020
Limited Partners Capital Account [Line Items]
Net income	$ 166	$ 167	$ 144	$ 142	$ 333	$ 286
Less: Net income attributable to noncontrolling interests	4		3		8	7
Net income attributable to the Partnership	$ 162		141		325	279
Distributions declared						323
Preferred unitholder’s interest in net income attributable to the Partnership			$ 12		$ 24	12
Distributions in excess of income						(56)
General Partner SPLC
Limited Partners Capital Account [Line Items]
Distributions declared						55
Distributions in excess of income						0
General Partner SPLC | Economic Interest
Limited Partners Capital Account [Line Items]
Noncontrolling interest							2.00%
Preferred Partner
Limited Partners Capital Account [Line Items]
Preferred unitholder’s interest in net income attributable to the Partnership						12
Limited Partners’ Common Units
Limited Partners Capital Account [Line Items]
Distributions declared						268
Distributions in excess of income						$ (56)

Net Income Per Limited Partne_4

Net Income Per Limited Partner Unit - Schedule of Basic and Diluted Net Income Per Unit (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Distribution Made To Limited Partner [Line Items]
Net income attributable to the Partnership’s common unitholders (basic)	$ 150	$ 129		$ 267
Dilutive effect of preferred units	12	12
Distributions declared				323
Distributions in excess of income				(56)
General Partner SPLC
Distribution Made To Limited Partner [Line Items]
Net income attributable to the Partnership’s common unitholders (basic)				55
Distributions declared				55
Distributions in excess of income				0
Limited Partners’ Common Units
Distribution Made To Limited Partner [Line Items]
Net income attributable to the Partnership’s common unitholders (basic)			$ 301	212
Dilutive effect of preferred units			24	12
Net income attributable to the Partnership’s common unitholders (diluted)	$ 162	$ 141	$ 325	224
Distributions declared				268
Distributions in excess of income				$ (56)
Weighted average units outstanding (in millions)
Weighted average units outstanding - Basic (in shares)	393.3	393.3	393.3	313.3
Dilutive effect of preferred units (in shares)	50.8	50.8	50.8
Weighted average units outstanding - Diluted (in shares)	444.1	444.1	444.1	338.7
Weighted average units outstanding, basic and diluted (in shares)				25.4
Net income per Limited Partner Unit (in dollars)
Net income per Limited Partner Unit - basic (in dollars per share)	$ 0.38	$ 0.33	$ 0.76	$ 0.68
Net income per Limited Partner Unit - diluted (in dollars per share)	$ 0.36	$ 0.32	$ 0.73	0.66
Net income per Limited Partner unit (in dollars per share)				$ 0.68

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 21, 2021	Apr. 01, 2020	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2021	Jun. 30, 2020
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per share)			$ 0.3000	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.4600	$ 0.7600	$ 0.9200
Payments to acquire assets										$ 4	$ 9
Preferred Units
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per share)		$ 0.2363	$ 0.2363							$ 0.4726
Subsequent Event | Common Units
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per share)	$ 0.3000
Subsequent Event | Preferred Units
Subsequent Event [Line Items]
Distributions paid per limited partner unit (in dollars per share)	$ 0.2363