Phillips 66 Partners (PSXP) 10-Q 30 Apr 21 2021 Q1 Quarterly report Financial data

Cover

Cover	3 Months Ended
	Mar. 31, 2021shares
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-36011
Entity Registrant Name	Phillips 66 Partners LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	38-3899432
Entity Address, Address Line One	2331 CityWest Blvd
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77042
City Area Code	855
Local Phone Number	283-9237
Title of 12(b) Security	Common Units, Representing Limited Partner Interests
Trading Symbol	PSXP
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	228,340,146
Entity Central Index Key	0001572910
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

Consolidated Statement of Incom

Consolidated Statement of Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues and Other Income
Total operating revenues	$ 252	$ 267
Equity in earnings of affiliates	124	136
Other income	0	1
Total revenues and other income	376	404
Costs and Expenses
Operating and maintenance expenses	95	88
Depreciation	34	30
Impairments	198	0
General and administrative expenses	17	17
Taxes other than income taxes	10	11
Interest and debt expense	33	29
Other expenses	0	2
Total costs and expenses	387	177
Income (loss) before income taxes	(11)	227
Income tax expense	0	1
Net Income (Loss)	(11)	226
Less: Net income attributable to noncontrolling interest	7	0
Net Income (Loss) Attributable to the Partnership	(18)	226
Less: Preferred unitholders’ interest in net income (loss) attributable to the Partnership	12	10
Limited Partners’ Interest in Net Income (Loss) Attributable to the Partnership	$ (30)	$ 216
Common Units
Net Income (Loss) Attributable to the Partnership Per Limited Partner Unit (dollars)
Common units - basic (in dollars per share)	$ (0.13)	$ 0.95
Common units - diluted (in dollars per share)	$ (0.13)	$ 0.93
Weighted-Average Limited Partner Units Outstanding (thousands)
Common units—basic (in shares)	228,340,146	228,312,261
Common units—diluted (in shares)	228,340,000	242,132,000
Third Party
Revenues and Other Income
Total operating revenues	$ 7	$ 9
Related Party
Revenues and Other Income
Total operating revenues	$ 245	$ 258

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (11)	$ 226
Defined benefit plans
Plan sponsored by equity affiliates, net of income taxes	(1)	0
Other comprehensive loss	(1)	0
Comprehensive Income (Loss)	(12)	226
Less: Comprehensive income attributable to noncontrolling interest	7	0
Comprehensive Income (Loss) Attributable to the Partnership	$ (19)	$ 226

Consolidated Balance Sheet

Consolidated Balance Sheet - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 3	$ 7
Accounts receivable—related parties	104	103
Accounts receivable—third parties	3	3
Materials and supplies	16	16
Prepaid expenses and other current assets	17	11
Total current assets	143	140
Equity investments	3,029	3,244
Net properties, plants and equipment	3,646	3,639
Goodwill	185	185
Other assets	50	50
Total Assets	7,053	7,258
Liabilities
Accounts payable—related parties	20	19
Accounts payable—third parties	54	73
Accrued interest	39	35
Deferred revenues	38	27
Short-term debt	500	465
Accrued property and other taxes	12	11
Other current liabilities	3	3
Total current liabilities	666	633
Long-term debt	3,444	3,444
Other liabilities	90	90
Total Liabilities	4,200	4,167
Equity
Accumulated other comprehensive loss	(2)	(1)
Total unitholders’ equity	2,566	2,798
Noncontrolling interest	287	293
Total Equity	2,853	3,091
Total Liabilities and Equity	7,053	7,258
Public | Preferred Units
Equity
Preferred unitholders (2021 and 2020—13,819,791 units issued and outstanding)	749	749
Total Equity	749	749
Public | Common Units
Equity
Common unitholders	2,647	2,706
Total Equity	2,647	2,706
Non-public | Common Units | Phillips 66
Equity
Common unitholders	(828)	(656)
Total Equity	$ (828)	$ (656)

Consolidated Balance Sheet (Par

Consolidated Balance Sheet (Parenthetical) - shares	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Public
Preferred units, issued (in shares)	13,819,791	13,819,791
Preferred units, outstanding (in shares)	13,819,791	13,819,791
Common Units | Public
Units issued (in shares)	58,580,009		58,580,009
Units outstanding (in shares)	58,580,009		58,580,009
Common Units | Non-public | Phillips 66
Units issued (in shares)	169,760,137	169,760,137
Units outstanding (in shares)	169,760,137	169,760,137

Consolidated Statement of Cash

Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities
Net income (loss)	$ (11)	$ 226
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation	34	30
Impairments	198	0
Undistributed equity earnings	(5)	4
Other	0	2
Working capital adjustments
Accounts receivable	(1)	10
Prepaid expenses and other current assets	(6)	(4)
Accounts payable	2	(3)
Accrued interest	4	4
Deferred revenues	11	3
Other accruals	1	2
Net Cash Provided by Operating Activities	227	274
Cash Flows From Investing Activities
Cash capital expenditures and investments	(78)	(236)
Liberty acquisition	0	(75)
Return of investment from equity affiliates	39	38
Net Cash Used in Investing Activities	(39)	(273)
Cash Flows From Financing Activities
Issuance of debt	450	0
Repayment of debt	(415)	0
Issuance of common units	0	2
Net proceeds from equity interest transfer	0	12
Distributions to noncontrolling interest	(13)	0
Other distributions to Phillips 66	(2)	0
Net Cash Used in Financing Activities	(192)	(195)
Net Change in Cash and Cash Equivalents	(4)	(194)
Cash and cash equivalents at beginning of period	7	286
Cash and Cash Equivalents at End of Period	3	92
Preferred Units
Cash Flows From Financing Activities
Quarterly distributions to unitholders	(12)	(9)
Public | Preferred Units
Cash Flows From Operating Activities
Net income (loss)	12	10
Public | Common Units
Cash Flows From Operating Activities
Net income (loss)	(8)	55
Cash Flows From Financing Activities
Quarterly distributions to unitholders	(51)	(51)
Phillips 66 | Non-public | Common Units
Cash Flows From Operating Activities
Net income (loss)	(22)	161
Cash Flows From Financing Activities
Quarterly distributions to unitholders	$ (149)	$ (149)

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Noncontrolling Interest	Accum. Other Comprehensive Loss	Preferred UnitsPublic	Common UnitsPublic	Common UnitsNon-publicPhillips 66
Beginning Balance at Dec. 31, 2019	$ 2,834	$ 0	$ (1)	$ 746	$ 2,717	$ (628)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common units	2				2
Net income (loss)	226			10	55	161
Other comprehensive loss	0
Quarterly cash distributions to unitholders and General Partner	(209)			(9)	(51)	(149)
Ending Balance at Mar. 31, 2020	$ 2,853	0	(1)	$ 747	$ 2,723	$ (616)
Beginning balance, Units (in shares) at Dec. 31, 2019	242,119,367			13,819,791	58,539,439	169,760,137
Units Outstanding [Roll Forward]
Units issued in public equity offerings (in shares)	40,570				40,570
Ending balance, Units (in shares) at Mar. 31, 2020	242,159,937			13,819,791	58,580,009	169,760,137
Beginning Balance at Dec. 31, 2020	$ 3,091	293	(1)	$ 749	$ 2,706	$ (656)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(11)	7		12	(8)	(22)
Other comprehensive loss	(1)		(1)
Quarterly cash distributions to unitholders and General Partner	(212)			(12)	(51)	(149)
Distributions to noncontrolling interest	(13)	(13)
Other distributions to Phillips 66	(1)					(1)
Ending Balance at Mar. 31, 2021	$ 2,853	$ 287	$ (2)	$ 749	$ 2,647	$ (828)
Beginning balance, Units (in shares) at Dec. 31, 2020	242,159,937			13,819,791	58,580,009	169,760,137
Units Outstanding [Roll Forward]
Units issued in public equity offerings (in shares)	0
Ending balance, Units (in shares) at Mar. 31, 2021	242,159,937			13,819,791	58,580,009	169,760,137

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Cash distributions per common unit (in dollars per share)	$ 0.875	$ 0.875

Description of the Business

Description of the Business	3 Months Ended
	Mar. 31, 2021
Description of Business [Abstract]
Description of the Business	Note 1—Description of the Business Unless otherwise stated or the context otherwise indicates, all references to “Phillips 66 Partners,” “the Partnership,” “us,” “our,” “we,” or similar expressions refer to Phillips 66 Partners LP, including its consolidated subsidiaries. References to Phillips 66 may refer to Phillips 66 and/or its subsidiaries, depending on the context. References to our “General Partner” or “GP” refer to Phillips 66 Partners GP LLC, and references to “Phillips 66 PDI” refer to Phillips 66 Project Development Inc., the Phillips 66 subsidiary that holds a limited partner interest in us and wholly owns our General Partner. We are a growth-oriented master limited partnership formed to own, operate, develop and acquire primarily fee-based midstream assets. Our operations consist of crude oil, refined petroleum products and natural gas liquids (NGL) transportation, terminaling, processing and storage assets. We conduct our operations through both wholly owned and joint venture operations. The majority of our wholly owned assets are associated with, and are integral to the operation of, nine of Phillips 66’s owned or joint venture refineries. Our operations consist of one reportable segment. We primarily generate revenue by providing fee-based transportation, terminaling, processing, storage and fractionation services to Phillips 66 and other customers. Our equity affiliates primarily generate revenue from transporting and terminaling crude oil, refined petroleum products and NGL. Since we do not own any of the crude oil, refined petroleum products and NGL we handle and do not engage in the trading of those commodities, we have limited direct exposure to risks associated with fluctuating commodity prices, although these risks indirectly influence our activities and results of operations over the long term.

Interim Financial Information

Interim Financial Information	3 Months Ended
	Mar. 31, 2021
Interim Financial Information [Abstract]
Interim Financial Information	Note 2—Interim Financial Information The unaudited interim financial information presented in the financial statements included in this report is prepared in accordance with generally accepted accounting principles in the United States (GAAP) and includes all known accruals and adjustments necessary, in the opinion of management, for a fair presentation of our financial position, results of operations and cash flows for the periods presented. Unless otherwise specified, all such adjustments are of a normal and recurring nature. Certain notes and other information have been condensed or omitted from the interim financial statements included in this report. Therefore, these interim financial statements should be read in conjunction with the audited consolidated financial statements and notes included in our 2020 Annual Report on Form 10-K. The results of operations for the three months ended March 31, 2021, are not necessarily indicative of the results to be expected for the full year. The COVID-19 pandemic continues to disrupt economic activities globally. Reduced demand for petroleum products has resulted in decreased volumes through logistics infrastructure. The depth and duration of the economic consequences of the COVID-19 pandemic remain uncertain. We continuously monitor our asset and investment portfolio for impairments in this challenging business environment. We recorded an impairment totaling $198 million in the first quarter of 2021, and additional impairments may be required in the future. See Note 4—Equity Investments for additional information.

Operating Revenues

Operating Revenues	3 Months Ended
	Mar. 31, 2021
Revenue from Contract with Customer [Abstract]
Operating Revenues	Note 3—Operating Revenues Operating revenues are primarily generated from long-term pipeline transportation, terminaling, storage, processing and fractionation lease and service agreements, mainly with Phillips 66. These agreements typically include escalation clauses to adjust transportation tariffs and terminaling and storage fees to reflect changes in price indices. In addition, most of these agreements contain renewal options, which typically require the mutual consent of both our customers and us. Total operating revenues disaggregated by asset type were as follows: Millions of Dollars Three Months Ended 2021 2020 Pipelines $ 104 111 Terminals 39 43 Storage, processing and other revenues 109 113 Total operating revenues $ 252 267 The majority of our agreements with Phillips 66 are considered operating leases under GAAP. The classification of a lease as either an operating or a financing lease requires judgment in assessing the contract’s lease and service components and in determining the asset’s fair value. We have elected to account for lease and service elements of contracts classified as leases on a combined basis, except for leases of processing-type assets, which contain non-ratable fees related to turnaround activity. For these types of leases, we continue to separate the lease and service elements based on relative standalone prices and apply the lease standard to the lease element and the revenue standard to the service element. Total operating revenues disaggregated by lease and service revenues were as follows: Millions of Dollars Three Months Ended 2021 2020 Lease revenues $ 207 218 Service revenues 45 49 Total operating revenues $ 252 267 Accounts Receivable We bill our customers, mainly Phillips 66, under our lease and service contracts generally on a monthly basis. Total accounts receivable by revenue type was as follows: Millions of Dollars March 31 December 31 Lease receivables $ 89 87 Service receivables 18 19 Total accounts receivable $ 107 106 Deferred Revenues Our deferred revenues represent payments received from our customers, mainly Phillips 66, in advance of the period in which lease and service contract performance obligations have been fulfilled. The majority of our deferred revenues relate to a tolling agreement and a storage agreement that are classified as leases. The remainder of our deferred revenues relate to lease and service agreements that contain minimum volume commitments with recovery provisions. Our deferred revenues are recorded in the “Deferred revenues” and “Other liabilities” line items on our consolidated balance sheet. Total deferred revenues under our lease and service agreements were as follows: Millions of Dollars March 31 December 31 Deferred lease revenues $ 54 45 Deferred service revenues 4 4 Total deferred revenues $ 58 49 Future Minimum Lease Payments from Customers At March 31, 2021, future minimum payments to be received under our lease agreements with customers, mainly Phillips 66, were estimated to be: Millions Remainder of 2021 $ 575 2022 752 2023 706 2024 588 2025 530 Remaining years 1,297 Total future minimum lease payments from customers $ 4,448 Remaining Performance Obligations We typically have long-term service contracts with our customers, mainly Phillips 66, of which the original durations range from 5 to 15 years. The weighted-average remaining duration of these contracts is 9 years. These contracts include both fixed and variable transaction price components. At March 31, 2021, future service revenues expected to be recognized for the fixed component of the transaction price of our remaining performance obligations from service contracts with our customers that have an original expected duration of greater than one year were: Millions Remainder of 2021 $ 99 2022 124 2023 123 2024 99 2025 95 Remaining years 381 Total future service revenues $ 921

Equity Investments

Equity Investments	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Investments	Note 4—Equity Investments The following table summarizes the carrying value of our equity investments: Millions of Dollars Percentage March 31 December 31 Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline) 25.00 % $ 575 577 Bayou Bridge Pipeline, LLC (Bayou Bridge) 40.00 281 288 DCP Sand Hills Pipeline, LLC (Sand Hills) 33.34 585 582 DCP Southern Hills Pipeline, LLC (Southern Hills) 33.34 217 217 Explorer Pipeline Company (Explorer) 21.94 89 92 Gray Oak Pipeline, LLC 65.00 843 860 Liberty Pipeline LLC (Liberty) 50.00 46 241 Paradigm Pipeline LLC (Paradigm) 50.00 140 141 Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal) 70.00 15 15 South Texas Gateway Terminal LLC (South Texas Gateway Terminal) 25.00 175 167 STACK Pipeline LLC (STACK) 50.00 63 64 Total equity investments $ 3,029 3,244 Earnings from our equity investments were as follows: Millions of Dollars Three Months Ended 2021 2020 Bakken Pipeline $ 44 57 Bayou Bridge 7 10 Sand Hills 27 41 Southern Hills 12 11 Explorer 3 7 Gray Oak Pipeline, LLC 21 5 Liberty — — Paradigm 5 4 Phillips 66 Partners Terminal — — South Texas Gateway Terminal 4 — STACK 1 1 Total equity in earnings of affiliates $ 124 136 Dakota Access, LLC (Dakota Access) and Energy Transfer Crude Oil Company, LLC (ETCO) In March 2019, a wholly owned subsidiary of Dakota Access issued $2.5 billion aggregate principal amount of senior unsecured notes. Dakota Access and ETCO have guaranteed repayment of the notes. In addition, we and our co-venturers in Dakota Access provided a Contingent Equity Contribution Undertaking (CECU) in conjunction with the notes offering. Under the CECU, the co-venturers may be severally required to make proportionate equity contributions to Dakota Access if there is an unfavorable final judgment in the ongoing litigation related to an easement granted by the U.S. Army Corps of Engineers (USACE) to allow the pipeline to be constructed under Lake Oahe in North Dakota. Contributions may be required if Dakota Access determines that the issues included in any such final judgment cannot be remediated and Dakota Access has or is projected to have insufficient funds to satisfy repayment of the notes. If Dakota Access undertakes remediation to cure issues raised in a final judgment, contributions may be required if any series of the notes become due, whether by acceleration or at maturity, during such time, to the extent Dakota Access has or is projected to have insufficient funds to pay such amounts. At March 31, 2021, our share of the maximum potential equity contributions under the CECU was approximately $631 million. In July 2020, the trial court presiding over the litigation vacated Dakota Access’ easement under Lake Oahe and ordered the Dakota Access Pipeline to be shut down and emptied of crude oil pending the preparation of an Environmental Impact Statement (EIS) by the USACE, which had been ordered by the court in March 2020 and is now expected to be completed by March 2022. In August 2020, pending an appeal of the trial court’s decisions, an appellate court denied Dakota Access’ motion to stay the order vacating the easement, but granted its motion to stay the order that the pipeline be shut down while the EIS is prepared. In January 2021, the appellate court affirmed the trial court’s order vacating the easement and directing the USACE to prepare an EIS and reversed the order directing the pipeline to be shut down. Notwithstanding that the easement has been vacated, in April 2021, the USACE indicated that it currently intends to allow the pipeline to continue to operate while it proceeds with the EIS. Currently, there is a motion for a permanent injunction to shut down the pipeline before the trial court that could be decided at any time. Additionally, Dakota Access has requested the appellate court to stay its January 2021 decision pending a filing and disposition of a petition for writ of certiorari to the U.S. Supreme Court. If the pipeline is required to cease operations, either permanently or pending the preparation of the EIS, and should Dakota Access and ETCO not have sufficient funds to pay ongoing expenses, we also could be required to support our share of the ongoing expenses, including scheduled interest payments on the notes of approximately $25 million annually, in addition to the potential obligations under the CECU. Summarized financial information for 100% of Dakota Access is as follows: Millions of Dollars Three Months Ended 2021 2020 Revenues $ 215 258 Income before income taxes 142 186 Net income 142 186 Gray Oak Pipeline, LLC Gray Oak Pipeline, LLC was formed to develop and construct the Gray Oak Pipeline, which transports crude oil from the Permian and Eagle Ford to Texas Gulf Coast destinations that include Corpus Christi and the Sweeny area, including the Phillips 66 Sweeny Refinery, as well as access to the Houston market. We have a consolidated holding company that owns 65% of Gray Oak Pipeline, LLC. In December 2018, a third party exercised its option to acquire a 35% interest in the holding company. Because the holding company’s sole asset was its ownership interest in Gray Oak Pipeline, LLC, which was considered a financial asset, and because certain restrictions were placed on the third party’s ability to transfer or sell its interest in the holding company during the construction of the Gray Oak Pipeline, the legal sale of the 35% interest did not qualify as a sale under GAAP at that time. The Gray Oak Pipeline commenced full operations in the second quarter of 2020 and the restrictions placed on the co-venturer were lifted on June 30, 2020, resulting in the recognition of the sale under GAAP. Accordingly, at June 30, 2020, the co-venturer’s 35% interest in the holding company was recharacterized from a long-term obligation to a noncontrolling interest on our consolidated balance sheet. We have an effective ownership interest of 42.25% in Gray Oak Pipeline, LLC, after considering our co-venturer’s 35% interest in the consolidated holding company. Liberty At March 31, 2021, we held a 50% interest in Liberty, a joint venture formed to develop and construct the Liberty Pipeline system. Liberty was considered a VIE because it did not have sufficient equity at risk to fully fund the construction of all assets required for principal operations. We determined we were not the primary beneficiary because we and our co-venturer jointly directed the activities of Liberty that most significantly impact economic performance. In the first quarter of 2021, we decided to exit the Liberty Pipeline project, which had previously been deferred due to the challenging business environment created by the COVID-19 pandemic. As a result, we recorded a $198 million impairment to reduce the book value of our investment in Liberty at March 31, 2021, to our share of the estimated fair value of the joint venture’s pipeline assets and net working capital. The impairment is included in the “Impairments” line item on our consolidated statement of income (loss). This valuation resulted in a Level 3 nonrecurring fair value measurement. At March 31, 2021, the book value of our investment in Liberty, and our maximum exposure to loss, was $46 million. In April 2021, we transferred our ownership interest in Liberty to our co-venturer for cash and certain pipeline assets with an estimated fair value that approximated our book value at March 31, 2021.

Net Income (Loss) Per Limited P

Net Income (Loss) Per Limited Partner Unit	3 Months Ended
	Mar. 31, 2021
Partners' Capital Notes [Abstract]
Net Income (Loss) Per Limited Partner Unit	Note 5—Net Income (Loss) Per Limited Partner Unit We calculate net income (loss) attributable to the Partnership per limited partner unit by dividing the limited partners’ interest in net income (loss) by the weighted-average number of common units outstanding for the period. After considering the period’s cash distributions declared, the remaining undistributed earnings or excess distributions declared over earnings, if any, are allocated to participating securities in accordance with the contractual terms of our partnership agreement and as prescribed under the two-class method for those periods in which we have participating securities. Our preferred units became participating securities effective October 1, 2020. See Note 9—Equity for additional information on our preferred units. For the diluted net income (loss) per limited partner unit calculation, the preferred units are assumed to be converted at the beginning of the period into common limited partner units on a one-for-one basis, and the distribution formula for available cash in our partnership agreement is recalculated, using the original available cash amount increased only for the preferred distributions declared which would not have been paid after conversion. Any potentially dilutive securities are excluded from the diluted earnings per unit computation if the effect of including such securities would be anti-dilutive. Millions of Dollars Three Months Ended 2021 2020 Net income (loss) attributable to the Partnership $ (18) 226 Less: Limited partners’ distributions declared on preferred units* 12 10 Limited partners’ distributions declared on common units* 200 199 Distributions less than (more than) net income (loss) attributable to the Partnership $ (230) 17 *Distributions declared are attributable to the indicated periods. Limited Limited Total Three Months Ended March 31, 2021 Net income (loss) attributable to the Partnership (millions) : Distributions declared $ 200 12 212 Distributions more than net income (loss) attributable to the Partnership (230) — (230) Net income (loss) attributable to the Partnership—basic (30) 12 (18) Dilutive effect of preferred units — Net income (loss) attributable to the Partnership—diluted $ (30) Weighted-average units outstanding—basic 228,340,146 Dilutive effect of preferred units — Weighted-average units outstanding—diluted 228,340,146 Net income (loss) attributable to the Partnership per limited partner unit—basic (dollars) $ (0.13) Net income (loss) attributable to the Partnership per limited partner unit—diluted (dollars) (0.13) Limited Limited Total Three Months Ended March 31, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 199 10 209 Distributions less than net income attributable to the Partnership 17 — 17 Net income attributable to the Partnership—basic 216 10 226 Dilutive effect of preferred units 10 Net income attributable to the Partnership—diluted $ 226 Weighted-average units outstanding—basic 228,312,261 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,132,052 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 0.95 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 0.93 On April 20, 2021, the Board of Directors of our General Partner declared a quarterly cash distribution of $0.875 per common unit, which will result in a total distribution of $200 million attributable to the first quarter of 2021. This distribution is payable on May 14, 2021, to common unitholders of record as of April 30, 2021. Beginning with the distribution to preferred unitholders attributable to the fourth quarter of 2020, the preferred unitholders are entitled to receive cumulative quarterly distributions equal to the greater of $0.678375 per unit, or the per-unit distribution amount paid to the common unitholders. Preferred unitholders will receive $12 million of distributions attributable to the first quarter of 2021. This distribution is payable May 14, 2021, to preferred unitholders of record as of April 30, 2021.

Properties, Plants and Equipmen

Properties, Plants and Equipment	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Properties, Plants and Equipment	Note 6—Properties, Plants and Equipment Our investment in properties, plants and equipment (PP&E), with the associated accumulated depreciation, was: Millions of Dollars March 31 December 31 Land $ 19 19 Buildings and improvements 116 115 Pipelines and related assets * 1,527 1,518 Terminals and related assets * 849 847 Rail racks and related assets * 137 137 Processing and related assets * 1,064 1,063 Caverns and related assets * 733 732 Construction-in-progress 420 394 Gross PP&E 4,865 4,825 Accumulated depreciation (1,219) (1,186) Net PP&E $ 3,646 3,639 *Assets for which we are the lessor.

Debt

Debt	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Debt	Note 7—Debt Millions of Dollars March 31 December 31 2.450% Senior Notes due December 2024 $ 300 300 3.605% Senior Notes due February 2025 500 500 3.550% Senior Notes due October 2026 500 500 3.750% Senior Notes due March 2028 500 500 3.150% Senior Notes due December 2029 600 600 4.680% Senior Notes due February 2045 450 450 4.900% Senior Notes due October 2046 625 625 Tax-exempt bonds due April 2021, at weighted-average rates of 0.260% and 0.360% at March 31, 2021, and December 31, 2020, respectively 50 50 Revolving credit facility borrowings due April 2021 at weighted-average rate of 1.345% 450 415 Debt at face value 3,975 3,940 Net unamortized discounts and debt issuance costs (31) (31) Total debt 3,944 3,909 Short-term debt (500) (465) Long-term debt $ 3,444 3,444 The fair value of our fixed-rate and floating-rate debt is estimated based on observable market prices and is classified as Level 2 of the fair value hierarchy. The fair value of our fixed-rate debt was $3,679 million and $3,752 million at March 31, 2021, and December 31, 2020, respectively. The fair value of our floating-rate debt approximated carrying value of $500 million and $465 million at March 31, 2021, and December 31, 2020, respectively. At March 31, 2021, and December 31, 2020, borrowings of $450 million and $415 million were outstanding under our $750 million revolving credit facility, respectively. At both March 31, 2021, and December 31, 2020, $1 million in letters of credit had been issued that were supported by this facility. Debt Repayment On April 1, 2021, we repaid the two remaining $25 million tranches of tax-exempt bonds due April 2021, totaling $50 million. Debt Issuance

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Note 8—Contingencies From time to time, lawsuits involving a variety of claims that arise in the ordinary course of business are filed against us. We also may be required to remove or mitigate the effects on the environment of the placement, storage, disposal or release of certain chemical, mineral and petroleum substances at various sites. We regularly assess the need for accounting recognition or disclosure of these contingencies. In the case of all known contingencies (other than those related to income taxes), we accrue a liability when the loss is probable and the amount is reasonably estimable. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum of the range is accrued. We do not reduce these liabilities for potential insurance or third-party recoveries. If applicable, we accrue receivables for probable insurance or other third-party recoveries. In the case of income-tax-related contingencies, we use a cumulative probability-weighted loss accrual in cases where sustaining a tax position is uncertain. Based on currently available information, we believe it is remote that future costs related to known contingent liability exposures will exceed current accruals by an amount that would have a material adverse impact on our consolidated financial statements. As we learn new facts concerning contingencies, we reassess our position both with respect to accrued liabilities and other potential exposures. Estimates particularly sensitive to future changes include any contingent liabilities recorded for environmental remediation, tax and legal matters. Estimated future environmental remediation costs are subject to change due to such factors as the uncertain magnitude of cleanup costs, the unknown time and extent of such remedial actions that may be required, and the determination of our liability in proportion to that of other potentially responsible parties. Estimated future costs related to tax and legal matters are subject to change as events evolve and as additional information becomes available during the administrative and litigation processes. Environmental We are subject to federal, state and local environmental laws and regulations. We record accruals for contingent environmental liabilities based on management’s best estimates, using all information that is available at the time. We measure estimates and base liabilities on currently available facts, existing technology, and presently enacted laws and regulations, taking into account stakeholder and business considerations. When measuring environmental liabilities, we also consider our prior experience in remediation of contaminated sites, other companies’ cleanup experience, and data released by the U.S. Environmental Protection Agency or other organizations. We consider unasserted claims in our determination of environmental liabilities, and we accrue them in the period they are both probable and reasonably estimable. At March 31, 2021, and December 31, 2020, our total environmental accruals were not material. In the future, we may be involved in additional environmental assessments, cleanups and proceedings. Legal Proceedings Under our amended omnibus agreement, Phillips 66 provides certain services for our benefit, including legal support services, and we pay an operational and administrative support fee for these services. Phillips 66’s legal organization applies its knowledge, experience and professional judgment to the specific characteristics of our cases, employing a litigation management process to manage and monitor the legal proceedings against us. The process facilitates the early evaluation and quantification of potential exposures in individual cases and enables tracking of those cases that have been scheduled for trial and/or mediation. Based on professional judgment and experience in using these litigation management tools and available information about current developments in all our cases, Phillips 66’s legal organization regularly assesses the adequacy of current accruals and determines if adjustment of existing accruals, or establishment of new accruals, is required. As of March 31, 2021, and December 31, 2020, we did not have any material accrued contingent liabilities associated with litigation matters. Indemnification and Excluded Liabilities Under our amended omnibus agreement and pursuant to the terms of various agreements under which we acquired assets from Phillips 66, Phillips 66 will indemnify us, or assume responsibility, for certain environmental liabilities, tax liabilities, litigation and any other liabilities attributable to the ownership or operation of the assets contributed to us and that arose prior to the effective date of each acquisition. These indemnifications and exclusions from liability have, in some cases, time limits and deductibles. When Phillips 66 performs under any of these indemnifications or exclusions from liability, we recognize noncash expenses and associated noncash capital contributions from our General Partner, as these are considered liabilities paid for by a principal unitholder.

Equity

Equity	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Equity	Note 9—Equity ATM Programs We have authorized an aggregate of $750 million under three $250 million continuous offerings of common units, or at-the-market (ATM) programs. The first two programs concluded in June 2018 and December 2019, respectively. We suspended issuances under the ATM program in the first quarter of 2020 due to low common unit prices. We did not issue any common units under the current ATM program during the three months ended March 31, 2021. Preferred Units Beginning with the distribution to preferred unitholders attributable to the fourth quarter of 2020, the preferred unitholders are entitled to receive cumulative quarterly distributions equal to the greater of $0.678375 per unit, or the per-unit distribution amount paid to the common unitholders as if such preferred units had converted into common units immediately prior to the record date. The holders of the preferred units may convert their preferred units into common units, on a one-for-one basis, at any time, in full or in part, subject to minimum conversion amounts and conditions.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Note 10—Related Party Transactions Commercial Agreements We have entered into long-term, fee-based commercial agreements with Phillips 66 to provide transportation, terminaling, storage, stevedoring, fractionation, processing, and rail terminal services. Under these agreements, Phillips 66 commits to provide us with minimum transportation, throughput or storage volumes, or minimum monthly service fees. If Phillips 66 does not meet its minimum volume commitments under an agreement, Phillips 66 pays us a deficiency payment based on the calculation described in the agreement. Amended and Restated Operational Services Agreement Under our amended and restated operational services agreement, we reimburse Phillips 66 for certain operational services provided in support of our pipelines, terminaling, processing, and storage facilities. These services include routine and emergency maintenance and repair services, routine operational activities, routine administrative services, construction and related services and such other services as we and Phillips 66 may mutually agree upon from time to time. Amended Omnibus Agreement The amended omnibus agreement addresses our payment of an operating and administrative support fee and our obligation to reimburse Phillips 66 for all other direct or allocated costs and expenses incurred by Phillips 66 in providing general and administrative services. Additionally, the omnibus agreement addresses Phillips 66’s indemnification to us and our indemnification to Phillips 66 for certain environmental and other liabilities. Further, it addresses the granting of a license from Phillips 66 to us with respect to the use of certain Phillips 66 trademarks. The operational and administrative support fee is for the provision of certain services, including: logistical services; asset oversight, such as operational management and supervision; corporate engineering services, including asset integrity and regulatory services; business development services; executive services; financial and administrative services (including treasury and accounting); information technology; legal services; corporate health, safety and environmental services; facility services; human resources services; procurement services; investor relations; tax matters; and public company reporting services. We pay Phillips 66 an operational and administrative support fee under the terms of our amended omnibus agreement in the amount of $8 million per month. We also reimburse Phillips 66 for all other direct or allocated costs incurred on behalf of us, pursuant to the terms of our amended omnibus agreement. The classification of these charges between operating and maintenance expenses and general and administrative expenses is based on the functional nature of the services performed for our operations. Under our amended and restated operational services agreement, we reimburse Phillips 66 for the provision of certain operational services in support of our operating assets. Additionally, we pay Phillips 66 for insurance services provided to us, and recoveries under these policies are recorded as an offset to our expenses. Operating and maintenance expenses also include volumetric gains and losses associated with volumes transported by Phillips 66. Tax Sharing Agreement Under our tax sharing agreement, we reimburse Phillips 66 for our share of state and local income and other taxes incurred by Phillips 66 due to our results of operations being included in a combined or consolidated tax return filed by Phillips 66. Any reimbursement is limited to the tax that we (and our subsidiaries) would have paid had we not been included in a combined group with Phillips 66. Phillips 66 may use its tax attributes to cause its combined or consolidated group to owe no tax; however, we would nevertheless reimburse Phillips 66 for the tax we would have owed, even though Phillips 66 had no cash expense for that period. Related Party Transactions Significant related party transactions included in our costs and expenses were: Millions of Dollars Three Months Ended 2021 2020 Operating and maintenance expenses $ 58 48 General and administrative expenses 15 17 Other related party balances were included in the following line items on our consolidated balance sheet, all of which were related to commercial agreements with Phillips 66: Millions of Dollars March 31 December 31 Prepaid expenses and other current assets $ 11 7 Other assets 47 47 Deferred revenues 38 27 Other current liabilities 1 1 Other liabilities 63 64 Equity Affiliate Arrangements In March 2019, we and our co-venturers in Dakota Access provided a CECU in conjunction with a senior unsecured notes offering. See Note 4—Equity Investments, for additional information.

Cash Flow Information

Cash Flow Information	3 Months Ended
	Mar. 31, 2021
Supplemental Cash Flow Information [Abstract]
Cash Flow Information	Note 11—Cash Flow Information Capital Expenditures and Investments Our capital expenditures and investments consisted of: Millions of Dollars Three Months Ended 2021 2020 Cash capital expenditures and investments $ 78 236 Change in capital expenditure accruals (20) (2) Total capital expenditures and investments $ 58 234

Net Income (Loss) Per Limited_2

Net Income (Loss) Per Limited Partner Unit (Policies)	3 Months Ended
	Mar. 31, 2021
Partners' Capital Notes [Abstract]
Net Income Per Limited Partner Unit	We calculate net income (loss) attributable to the Partnership per limited partner unit by dividing the limited partners’ interest in net income (loss) by the weighted-average number of common units outstanding for the period. After considering the period’s cash distributions declared, the remaining undistributed earnings or excess distributions declared over earnings, if any, are allocated to participating securities in accordance with the contractual terms of our partnership agreement and as prescribed under the two-class method for those periods in which we have participating securities.

Operating Revenues (Tables)

Operating Revenues (Tables)	3 Months Ended
	Mar. 31, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Total operating revenues disaggregated by asset type were as follows: Millions of Dollars Three Months Ended 2021 2020 Pipelines $ 104 111 Terminals 39 43 Storage, processing and other revenues 109 113 Total operating revenues $ 252 267 Total operating revenues disaggregated by lease and service revenues were as follows: Millions of Dollars Three Months Ended 2021 2020 Lease revenues $ 207 218 Service revenues 45 49 Total operating revenues $ 252 267
Accounts Receivable	Total accounts receivable by revenue type was as follows: Millions of Dollars March 31 December 31 Lease receivables $ 89 87 Service receivables 18 19 Total accounts receivable $ 107 106
Deferred Revenues	Total deferred revenues under our lease and service agreements were as follows: Millions of Dollars March 31 December 31 Deferred lease revenues $ 54 45 Deferred service revenues 4 4 Total deferred revenues $ 58 49
Schedule of Future Minimum Payments Receivable	At March 31, 2021, future minimum payments to be received under our lease agreements with customers, mainly Phillips 66, were estimated to be: Millions Remainder of 2021 $ 575 2022 752 2023 706 2024 588 2025 530 Remaining years 1,297 Total future minimum lease payments from customers $ 4,448
Expected Timing of Satisfaction	At March 31, 2021, future service revenues expected to be recognized for the fixed component of the transaction price of our remaining performance obligations from service contracts with our customers that have an original expected duration of greater than one year were: Millions Remainder of 2021 $ 99 2022 124 2023 123 2024 99 2025 95 Remaining years 381 Total future service revenues $ 921

Equity Investments (Tables)

Equity Investments (Tables)	3 Months Ended
	Mar. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Equity Investments	The following table summarizes the carrying value of our equity investments: Millions of Dollars Percentage March 31 December 31 Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline) 25.00 % $ 575 577 Bayou Bridge Pipeline, LLC (Bayou Bridge) 40.00 281 288 DCP Sand Hills Pipeline, LLC (Sand Hills) 33.34 585 582 DCP Southern Hills Pipeline, LLC (Southern Hills) 33.34 217 217 Explorer Pipeline Company (Explorer) 21.94 89 92 Gray Oak Pipeline, LLC 65.00 843 860 Liberty Pipeline LLC (Liberty) 50.00 46 241 Paradigm Pipeline LLC (Paradigm) 50.00 140 141 Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal) 70.00 15 15 South Texas Gateway Terminal LLC (South Texas Gateway Terminal) 25.00 175 167 STACK Pipeline LLC (STACK) 50.00 63 64 Total equity investments $ 3,029 3,244 Earnings from our equity investments were as follows: Millions of Dollars Three Months Ended 2021 2020 Bakken Pipeline $ 44 57 Bayou Bridge 7 10 Sand Hills 27 41 Southern Hills 12 11 Explorer 3 7 Gray Oak Pipeline, LLC 21 5 Liberty — — Paradigm 5 4 Phillips 66 Partners Terminal — — South Texas Gateway Terminal 4 — STACK 1 1 Total equity in earnings of affiliates $ 124 136 Summarized financial information for 100% of Dakota Access is as follows: Millions of Dollars Three Months Ended 2021 2020 Revenues $ 215 258 Income before income taxes 142 186 Net income 142 186

Net Income (Loss) Per Limited_3

Net Income (Loss) Per Limited Partner Unit (Tables)	3 Months Ended
	Mar. 31, 2021
Partners' Capital Notes [Abstract]
Schedule of Distributions Declared, Partners Interest in Partnership Net Income and Net Income per Unit by Class	Any potentially dilutive securities are excluded from the diluted earnings per unit computation if the effect of including such securities would be anti-dilutive. Millions of Dollars Three Months Ended 2021 2020 Net income (loss) attributable to the Partnership $ (18) 226 Less: Limited partners’ distributions declared on preferred units* 12 10 Limited partners’ distributions declared on common units* 200 199 Distributions less than (more than) net income (loss) attributable to the Partnership $ (230) 17 *Distributions declared are attributable to the indicated periods. Limited Limited Total Three Months Ended March 31, 2021 Net income (loss) attributable to the Partnership (millions) : Distributions declared $ 200 12 212 Distributions more than net income (loss) attributable to the Partnership (230) — (230) Net income (loss) attributable to the Partnership—basic (30) 12 (18) Dilutive effect of preferred units — Net income (loss) attributable to the Partnership—diluted $ (30) Weighted-average units outstanding—basic 228,340,146 Dilutive effect of preferred units — Weighted-average units outstanding—diluted 228,340,146 Net income (loss) attributable to the Partnership per limited partner unit—basic (dollars) $ (0.13) Net income (loss) attributable to the Partnership per limited partner unit—diluted (dollars) (0.13) Limited Limited Total Three Months Ended March 31, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 199 10 209 Distributions less than net income attributable to the Partnership 17 — 17 Net income attributable to the Partnership—basic 216 10 226 Dilutive effect of preferred units 10 Net income attributable to the Partnership—diluted $ 226 Weighted-average units outstanding—basic 228,312,261 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,132,052 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 0.95 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 0.93

Properties, Plants and Equipm_2

Properties, Plants and Equipment (Tables)	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Summary of Property, Plant and Equipment	Our investment in properties, plants and equipment (PP&E), with the associated accumulated depreciation, was: Millions of Dollars March 31 December 31 Land $ 19 19 Buildings and improvements 116 115 Pipelines and related assets * 1,527 1,518 Terminals and related assets * 849 847 Rail racks and related assets * 137 137 Processing and related assets * 1,064 1,063 Caverns and related assets * 733 732 Construction-in-progress 420 394 Gross PP&E 4,865 4,825 Accumulated depreciation (1,219) (1,186) Net PP&E $ 3,646 3,639 *Assets for which we are the lessor.

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Debt	Millions of Dollars March 31 December 31 2.450% Senior Notes due December 2024 $ 300 300 3.605% Senior Notes due February 2025 500 500 3.550% Senior Notes due October 2026 500 500 3.750% Senior Notes due March 2028 500 500 3.150% Senior Notes due December 2029 600 600 4.680% Senior Notes due February 2045 450 450 4.900% Senior Notes due October 2046 625 625 Tax-exempt bonds due April 2021, at weighted-average rates of 0.260% and 0.360% at March 31, 2021, and December 31, 2020, respectively 50 50 Revolving credit facility borrowings due April 2021 at weighted-average rate of 1.345% 450 415 Debt at face value 3,975 3,940 Net unamortized discounts and debt issuance costs (31) (31) Total debt 3,944 3,909 Short-term debt (500) (465) Long-term debt $ 3,444 3,444

Related Party Transactions (Tab

Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Summary of Related Party Transactions	Significant related party transactions included in our costs and expenses were: Millions of Dollars Three Months Ended 2021 2020 Operating and maintenance expenses $ 58 48 General and administrative expenses 15 17 Other related party balances were included in the following line items on our consolidated balance sheet, all of which were related to commercial agreements with Phillips 66: Millions of Dollars March 31 December 31 Prepaid expenses and other current assets $ 11 7 Other assets 47 47 Deferred revenues 38 27 Other current liabilities 1 1 Other liabilities 63 64

Cash Flow Information (Tables)

Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2021
Supplemental Cash Flow Information [Abstract]
Summary of Capital Expenditures and Noncash Investing and Financing Activities	Our capital expenditures and investments consisted of: Millions of Dollars Three Months Ended 2021 2020 Cash capital expenditures and investments $ 78 236 Change in capital expenditure accruals (20) (2) Total capital expenditures and investments $ 58 234

Description of the Business (De

Description of the Business (Details)	3 Months Ended
	Mar. 31, 2021refinerysegment
Property, Plant and Equipment [Line Items]
Number of reportable segments | segment	1
Phillips 66
Property, Plant and Equipment [Line Items]
Number of refineries | refinery	9

Interim Financial Information (

Interim Financial Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Interim Financial Information [Abstract]
Impairments	$ 198	$ 0

Operating Revenues - Revenues D

Operating Revenues - Revenues Disaggregated (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	$ 252	$ 267
Pipelines
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	104	111
Terminals
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	39	43
Storage, processing and other revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	$ 109	$ 113

Operating Revenues - Operating

Operating Revenues - Operating Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	$ 252	$ 267
Lease revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	207	218
Service revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total operating revenues	$ 45	$ 49

Operating Revenues - Accounts R

Operating Revenues - Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Revenue from External Customer [Line Items]
Total accounts receivable	$ 107	$ 106
Lease receivables
Revenue from External Customer [Line Items]
Total accounts receivable	89	87
Service receivables
Revenue from External Customer [Line Items]
Total accounts receivable	$ 18	$ 19

Operating Revenues - Deferred R

Operating Revenues - Deferred Revenue (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Revenue from External Customer [Line Items]
Total deferred revenues	$ 58	$ 49
Deferred lease revenues
Revenue from External Customer [Line Items]
Total deferred revenues	54	45
Deferred service revenues
Revenue from External Customer [Line Items]
Total deferred revenues	$ 4	$ 4

Operating Revenues - Schedule o

Operating Revenues - Schedule of Future Minimum Operating Lease Income (Details) $ in Millions	Mar. 31, 2021USD ($)
Revenue from Contract with Customer [Abstract]
Remainder of 2021	$ 575
2022	752
2023	706
2024	588
2025	530
Remaining years	1,297
Total future minimum lease payments from customers	$ 4,448

Operating Revenues - Narrative

Operating Revenues - Narrative (Details)	3 Months Ended
	Mar. 31, 2021
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer contracts, average remaining duration	9 years
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer contracts, term	5 years
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer contracts, term	15 years

Operating Revenues - Performanc

Operating Revenues - Performance Obligations (Details) $ in Millions	Mar. 31, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 921
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 99
Revenue, remaining performance obligation, expected timing of satisfaction, period	9 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]
Remaining performance obligation, amount	$ 124
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]
Remaining performance obligation, amount	$ 123
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]
Remaining performance obligation, amount	$ 99
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]
Remaining performance obligation, amount	$ 95
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 381
Revenue, remaining performance obligation, expected timing of satisfaction, period

Equity Investments - Schedule o

Equity Investments - Schedule of Carrying Value Equity Investments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 3,029	$ 3,244
Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	25.00%
Carrying Value	$ 575	577
Bayou Bridge Pipeline, LLC (Bayou Bridge)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	40.00%
Carrying Value	$ 281	288
DCP Sand Hills Pipeline, LLC (Sand Hills)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	33.34%
Carrying Value	$ 585	582
DCP Southern Hills Pipeline, LLC (Southern Hills)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	33.34%
Carrying Value	$ 217	217
Explorer Pipeline Company (Explorer)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	21.94%
Carrying Value	$ 89	92
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	65.00%
Carrying Value	$ 843	860
Liberty Pipeline LLC (Liberty)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value		241
Paradigm Pipeline LLC (Paradigm)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value	$ 140	141
Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	70.00%
Carrying Value	$ 15	15
South Texas Gateway Terminal LLC (South Texas Gateway Terminal)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	25.00%
Carrying Value	$ 175	167
STACK Pipeline LLC (STACK)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value	$ 63	$ 64

Equity Investments - Schedule_2

Equity Investments - Schedule of Equity Investment Earnings (Losses) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	$ 124	$ 136
Bakken Pipeline
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	44	57
Bayou Bridge
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	7	10
Sand Hills
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	27	41
Southern Hills
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	12	11
Explorer
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	3	7
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	21	5
Liberty
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	0	0
Paradigm
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	5	4
Phillips 66 Partners Terminal
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	0	0
South Texas Gateway Terminal
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	4	0
STACK
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	$ 1	$ 1

Equity Investments - Narrative

Equity Investments - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2021	Mar. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Impairments	$ 198,000,000	$ 0
Dakota Access, LLC | Senior Notes
Schedule of Equity Method Investments [Line Items]
Debt instrument, face amount				$ 2,500,000,000
Dakota Access and ETCO | Forecast
Schedule of Equity Method Investments [Line Items]
Scheduled annual interest payments			$ 25,000,000
Dakota Access and ETCO
Schedule of Equity Method Investments [Line Items]
Maximum exposure, undiscounted	$ 631,000,000
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest acquired, percentage	65.00%
Effective ownership interest	42.25%
Gray Oak Pipeline, LLC | Gray Oak Holdings LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest acquired, percentage	65.00%
Gray Oak Holdings LLC | Third Party
Schedule of Equity Method Investments [Line Items]
Percentage of ownership					35.00%
Liberty Pipeline LLC (Liberty)
Schedule of Equity Method Investments [Line Items]
Ownership interest acquired, percentage	50.00%
Impairments	$ 198,000,000
VIE, reporting entity involvement, maximum exposure	$ 46,000,000

Equity Investments - Schedule_3

Equity Investments - Schedule of Dakota Access (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Revenues	$ 252	$ 267
Income before income taxes	(11)	227
Net income (loss)	(18)	226
Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Revenues	215	258
Income before income taxes	142	186
Net income (loss)	$ 142	$ 186

Net Income (Loss) Per Limited_4

Net Income (Loss) Per Limited Partner Unit - Narrative (Details) $ / shares in Units, $ in Millions	May 14, 2021USD ($)$ / shares	Apr. 20, 2021USD ($)$ / shares	Mar. 31, 2021$ / shares	Dec. 31, 2020$ / shares	Mar. 31, 2020$ / shares
Subsequent Event [Line Items]
Conversion ratio of preferred units to common units			1	1
Cash distributions per common unit (in dollars per share)			$ 0.875		$ 0.875
Common Units | Cash Distribution | Subsequent Event
Subsequent Event [Line Items]
Cash distributions per common unit (in dollars per share)	$ 0.875
Distribution made to limited partner, distributions declared, per unit (in dollars per share)		$ 0.875
Distribution made to limited partner, cash distributions paid | $		$ 200
Distribution made to limited partner, cash distributions declared | $	$ 200
Preferred Units | Cash Distribution
Subsequent Event [Line Items]
Cash distributions per common unit (in dollars per share)				$ 0.678375
Distribution made to limited partner, distributions declared, per unit (in dollars per share)				$ 0.678375
Preferred Units | Cash Distribution | Subsequent Event
Subsequent Event [Line Items]
Distribution made to limited partner, cash distributions paid | $	$ 12
Distribution made to limited partner, cash distributions declared | $		$ 12

Net Income (Loss) Per Limited_5

Net Income (Loss) Per Limited Partner Unit - Schedule of Earnings Per unit of our Limited Partners (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Limited Partners' Capital Account [Line Items]
Net income (loss) attributable to the Partnership	$ (18)	$ 226
Less:
Distributions declared	212	209
Distributions less than (more than) net income (loss) attributable to the Partnership	(230)	17
Preferred Units | Limited Partner
Limited Partners' Capital Account [Line Items]
Net income (loss) attributable to the Partnership	12	10
Less:
Distributions declared	12	10
Common Units | Limited Partner
Limited Partners' Capital Account [Line Items]
Net income (loss) attributable to the Partnership	(30)	216
Less:
Distributions declared	$ 200	$ 199

Net Income (Loss) Per Limited_6

Net Income (Loss) Per Limited Partner Unit - Schedule of Net Income By Class of Participating Securities (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Limited Partners' Capital Account [Line Items]
Distributions declared	$ 212	$ 209
Distributions more than net income (loss) attributable to the Partnership	(230)	17
Net income (loss) attributable to the Partnership	$ (18)	$ 226
Limited Partners’ Common Units
Limited Partners' Capital Account [Line Items]
Weighted-average units outstanding—basic (in shares)	228,340,146	228,312,261
Dilutive effect of preferred units (in shares)	0	13,819,791
Weighted-average units outstanding—diluted (in shares)	228,340,146	242,132,052
Net income attributable to the Partnership per limited partner unit—basic (in dollars per share)	$ (0.13)	$ 0.95
Net income attributable to the Partnership per limited partner unit—diluted (in dollars per share)	$ (0.13)	$ 0.93
Limited Partner | Limited Partners’ Common Units
Limited Partners' Capital Account [Line Items]
Distributions declared	$ 200	$ 199
Distributions more than net income (loss) attributable to the Partnership	(230)	17
Net income (loss) attributable to the Partnership	(30)	216
Dilutive effect of preferred units	0	10
Net income (loss) attributable to the Partnership—diluted	(30)	226
Limited Partner | Limited Partners’ Preferred Units
Limited Partners' Capital Account [Line Items]
Distributions declared	12	10
Distributions more than net income (loss) attributable to the Partnership	0	0
Net income (loss) attributable to the Partnership	$ 12	$ 10

Properties, Plants and Equipm_3

Properties, Plants and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 4,865	$ 4,825
Accumulated depreciation	(1,219)	(1,186)
Net PP&E	3,646	3,639
Land
Property, Plant and Equipment [Line Items]
Gross PP&E	19	19
Buildings and improvements
Property, Plant and Equipment [Line Items]
Gross PP&E	116	115
Pipelines and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	1,527	1,518
Terminals and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	849	847
Rail racks and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	137	137
Processing and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	1,064	1,063
Caverns and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	733	732
Construction-in-progress
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 420	$ 394

Debt - Summary of Debt (Details

Debt - Summary of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt at face value	$ 3,975	$ 3,940
Net unamortized discounts and debt issuance costs	(31)	(31)
Total debt	3,944	3,909
Short-term debt	(500)	(465)
Long-term debt	3,444	3,444
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 450	415
Interest rate, stated percentage	1.345%
Tax-exempt bonds due April 2021, at weighted-average rates of 0.260% and 0.360% at March 31, 2021, and December 31, 2020, respectively
Debt Instrument [Line Items]
Long-term debt, gross	$ 50	$ 50
Interest rate, stated percentage	0.26%	0.36%
Senior Notes | 2.450% Senior Notes due December 2024
Debt Instrument [Line Items]
Long-term debt, gross	$ 300	$ 300
Interest rate, stated percentage	2.45%
Senior Notes | 3.605% Senior Notes due February 2025
Debt Instrument [Line Items]
Long-term debt, gross	$ 500	500
Interest rate, stated percentage	3.605%
Senior Notes | 3.550% Senior Notes due October 2026
Debt Instrument [Line Items]
Long-term debt, gross	$ 500	500
Interest rate, stated percentage	3.55%
Senior Notes | 3.750% Senior Notes due March 2028
Debt Instrument [Line Items]
Long-term debt, gross	$ 500	500
Interest rate, stated percentage	3.75%
Senior Notes | 3.150% Senior Notes due December 2029
Debt Instrument [Line Items]
Long-term debt, gross	$ 600	600
Interest rate, stated percentage	3.15%
Senior Notes | 4.680% Senior Notes due February 2045
Debt Instrument [Line Items]
Long-term debt, gross	$ 450	450
Interest rate, stated percentage	4.68%
Senior Notes | 4.900% Senior Notes due October 2046
Debt Instrument [Line Items]
Long-term debt, gross	$ 625	$ 625
Interest rate, stated percentage	4.90%

Debt - Narrative (Details)

Debt - Narrative (Details) $ in Millions	Apr. 06, 2021USD ($)	Apr. 01, 2021USD ($)tranche	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Line of credit facility, outstanding			$ 450		$ 415
Letters of credit outstanding, amount			1		1
Repayments of debt			415	$ 0
Short-term debt			500		465
Tax-Exempt Bonds | Subsequent Event
Debt Instrument [Line Items]
Number of tranches remaining | tranche		2
Repayments of debt		$ 25
Short-term debt		$ 50
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			750
Line of Credit | Short-term Debt | Subsequent Event
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 450
Line of Credit | Short-term Debt | Subsequent Event | Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate	0.875%
Fair Value, Inputs, Level 2 | Tax-Exempt Bonds
Debt Instrument [Line Items]
Debt instrument, fair value disclosure			500		465
Fair Value, Inputs, Level 2 | Senior Notes
Debt Instrument [Line Items]
Debt instrument, fair value disclosure			$ 3,679		$ 3,752

Equity (Details)

Equity (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)offering$ / sharesshares	Dec. 31, 2020$ / shares	Mar. 31, 2020$ / sharesshares	Dec. 31, 2019offering
Limited Partners' Capital Account [Line Items]
Number of common units issued in public offering (in shares) | shares	0		40,570
Cash distributions per common unit (in dollars per share)	$ 0.875		$ 0.875
Conversion ratio of preferred units to common units	1	1
Preferred Units | Cash Distribution
Limited Partners' Capital Account [Line Items]
Cash distributions per common unit (in dollars per share)		$ 0.678375
Distribution made to limited partner, distributions declared, per unit (in dollars per share)		$ 0.678375
At The Market Offering Program
Limited Partners' Capital Account [Line Items]
Aggregate authorized amount | $	$ 750
At The Market Offering Program | Common Units
Limited Partners' Capital Account [Line Items]
Number of continuous offerings | offering	3
Authorized amount per program | $	$ 250
Number Of Continuous Offerings Concluded | offering				2
Number of common units issued in public offering (in shares) | shares	0

Related Party Transactions - Na

Related Party Transactions - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)
Phillips 66 | Phillips 66 | Amended Omnibus Agreement
Related Party Transaction [Line Items]
Monthly operational and administrative support fee	$ 8

Related Party Transactions - Su

Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Related Party Transactions [Abstract]
Operating and maintenance expenses	$ 58	$ 48
General and administrative expenses	$ 15	$ 17

Related Party Transactions - Ot

Related Party Transactions - Other Related Party Balances (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	$ 17	$ 11
Other assets	50	50
Deferred revenues	38	27
Other current liabilities	3	3
Other liabilities	90	90
Phillips 66
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	11	7
Other assets	47	47
Deferred revenues	38	27
Other current liabilities	1	1
Other liabilities	$ 63	$ 64

Cash Flow Information (Details)

Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Supplemental Cash Flow Information [Abstract]
Cash capital expenditures and investments	$ 78	$ 236
Change in capital expenditure accruals	(20)	(2)
Total capital expenditures and investments	$ 58	$ 234