Phillips 66 Partners (PSXP) 10-Q30 Oct 202020 Q3 Quarterly reportFinancial data

Company Profile

Cover Page

Cover Page	9 Months Ended
Cover Page	Sep. 30, 2020shares
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
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	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Statement of Incom

Consolidated Statement of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Consolidated Statement of Income - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues and Other Income
Operating revenues	$ 265	$ 270	$ 773	$ 835
Equity in earnings of affiliates	129	139	369	395
Gain from equity interest transfer	0	0	84	0
Other income	0	2	2	5
Total revenues and other income	394	411	1,228	1,235
Costs and Expenses
Operating and maintenance expenses	85	91	257	315
Depreciation	35	30	96	88
General and administrative expenses	16	16	50	51
Taxes other than income taxes	9	10	30	30
Interest and debt expense	32	26	89	80
Other expenses	0	0	7	0
Total costs and expenses	177	173	529	564
Income before income taxes	217	238	699	671
Income tax expense	1	1	2	3
Net Income	216	237	697	668
Less: Net income attributable to noncontrolling interest	10	0	10	0
Net Income Attributable to the Partnership	206	237	687	668
Less: Preferred unitholders’ interest in net income attributable to the Partnership	10	9	29	28
Less: General partner’s interest in net income attributable to the Partnership	0	0	0	140
Limited Partners’ Interest in Net Income Attributable to the Partnership	$ 196	$ 228	$ 658	$ 500
Common Units
Net Income Attributable to the Partnership Per Limited Partner Unit (dollars)
Common units - basic (in dollars per share)	$ 0.86	$ 1.18	$ 2.88	$ 3.39
Common units - diluted (in dollars per share)	$ 0.85	$ 1.15	$ 2.84	$ 3.25
Weighted-Average Limited Partner Units Outstanding (thousands)
Common units—basic (in shares)	228,340,146	192,273,672	228,330,885	147,367,681
Common units—diluted (in shares)	242,160,000	206,093,000	242,151,000	161,187,000
Third Party
Revenues and Other Income
Operating revenues	$ 9	$ 8	$ 23	$ 21
Related Party
Revenues and Other Income
Operating revenues	$ 256	$ 262	$ 750	$ 814

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 216	$ 237	$ 697	$ 668
Defined benefit plans
Plan sponsored by equity affiliates, net of income taxes	0	0	0	0
Other comprehensive income	0	0	0	0
Comprehensive Income	216	237	697	668
Less: Comprehensive income attributable to noncontrolling interest	10	0	10	0
Comprehensive Income Attributable to the Partnership	$ 206	$ 237	$ 687	$ 668

Consolidated Balance Sheet

Consolidated Balance Sheet - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 2	$ 286
Accounts receivable—related parties	85	101
Accounts receivable—third parties	3	4
Materials and supplies	14	13
Prepaid expenses and other current assets	7	10
Total current assets	111	414
Equity investments	3,373	2,961
Net properties, plants and equipment	3,575	3,349
Goodwill	185	185
Other assets	50	52
Total Assets	7,294	6,961
Liabilities
Accounts payable—related parties	17	19
Accounts payable—third parties	104	84
Accrued interest	39	42
Deferred revenues	22	16
Short-term debt	340	25
Accrued property and other taxes	28	10
Other current liabilities	3	3
Total current liabilities	553	199
Long-term debt	3,443	3,491
Obligation from equity interest transfer	0	343
Other liabilities	91	94
Total Liabilities	4,087	4,127
Equity
Accumulated other comprehensive loss	(1)	(1)
Total unitholders’ equity	2,902	2,834
Noncontrolling interest	305	0
Total Equity	3,207	2,834
Total Liabilities and Equity	7,294	6,961
Public \| Preferred Units
Equity
Preferred unitholders (2020 and 2019—13,819,791 units issued and outstanding)	747	746
Total Equity	747	746
Public \| Common Units
Equity
Common unitholders	2,734	2,717
Total Equity	2,734	2,717
Non-public \| Common Units \| Phillips 66
Equity
Common unitholders	(578)	(628)
Total Equity	$ (578)	$ (628)

Consolidated Balance Sheet (Par

Consolidated Balance Sheet (Parenthetical) - shares	Sep. 30, 2020	Dec. 31, 2019
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	58,539,439
Units outstanding (in shares)	58,580,009	58,539,439
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	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash Flows From Operating Activities
Net income	$ 697	$ 668
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation	96	88
Undistributed equity earnings	9	7
Gain from equity interest transfer	(84)	0
Other	7	8
Working capital adjustments
Accounts receivable	17	(7)
Materials and supplies	(1)	0
Prepaid expenses and other current assets	3	15
Accounts payable	20	7
Accrued interest	(3)	(3)
Deferred revenues	6	(44)
Other accruals	18	18
Net Cash Provided by Operating Activities	785	757
Cash Flows From Investing Activities
Cash capital expenditures and investments	(796)	(924)
Advances/loans—related party	0	(95)
Collection of advances/loans—related party	0	95
Liberty acquisition	(75)	0
Return of investment from equity affiliates	124	52
Proceeds from sale of equity interest	0	81
Net Cash Used in Investing Activities	(747)	(791)
Cash Flows From Financing Activities
Issuance of debt	290	1,758
Repayment of debt	(25)	(985)
Issuance of common units	2	133
Debt issuance costs	0	(6)
Net proceeds from equity interest transfer	40	341
Proceeds from noncontrolling interest	3	0
Distributions to noncontrolling interest	(13)	0
Other distributions from (to) Phillips 66	8	(3)
Net Cash Provided by (Used in) Financing Activities	(322)	688
Net Change in Cash and Cash Equivalents	(284)	654
Cash and cash equivalents at beginning of period	286	1
Cash and Cash Equivalents at End of Period	2	655
Preferred Units
Cash Flows From Financing Activities
Quarterly distributions to unitholders	(28)	(28)
Public \| Preferred Units
Cash Flows From Operating Activities
Net income	29	28
Public \| Common Units
Cash Flows From Operating Activities
Net income	168	189
Cash Flows From Financing Activities
Quarterly distributions to unitholders	(153)	(142)
General Partner
Cash Flows From Operating Activities
Net income		140
Cash Flows From Financing Activities
Quarterly distributions to unitholders	0	(206)
Phillips 66 \| Non-public \| Common Units
Cash Flows From Operating Activities
Net income	490	311
Cash Flows From Financing Activities
Quarterly distributions to unitholders	$ (446)	$ (174)

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Noncontrolling Interest	Cumulative Effect, Period of Adoption, Adjustment	Accum. Other Comprehensive Loss	General Partner	Preferred UnitsPublic	Common UnitsPublic	Common UnitsPublicCumulative Effect, Period of Adoption, Adjustment	Common UnitsNon-publicPhillips 66
Beginning Balance at Dec. 31, 2018	$ 2,509	$ 0	$ (1)	$ (1)	$ (1,313)	$ 746	$ 2,485	$ (1)	$ 592
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common units	133						133
Net income	668				140	28	189		311
Quarterly cash distributions to unitholders and General Partner	(550)				(206)	(28)	(142)		(174)
Conversion of GP economic interest	(3)				1,381				(1,384)
Other distributions to Phillips 66	(2)				(2)
Ending Balance at Sep. 30, 2019	$ 2,754	0		(1)	$ 0	$ 746	$ 2,664		$ (655)
Beginning balance, Units (in shares) at Dec. 31, 2018	140,403,897				2,480,051	13,819,791	55,343,918		68,760,137
Units Outstanding [Roll Forward]
Units issued in public equity offerings (in shares)	2,470,037						2,470,037
Units issued in conversion of GP economic interest (in shares)	98,519,949				(2,480,051)				101,000,000
Ending balance, Units (in shares) at Sep. 30, 2019	241,393,883				0	13,819,791	57,813,955		169,760,137
Beginning Balance at Jun. 30, 2019	$ 2,616	0		(1)	$ (1,310)	$ 746	$ 2,555		$ 626
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common units	91						91
Net income	237					9	67		161
Quarterly cash distributions to unitholders and General Partner	(186)				(70)	(9)	(49)		(58)
Conversion of GP economic interest	(3)				1,381				(1,384)
Other distributions to Phillips 66	(1)				(1)
Ending Balance at Sep. 30, 2019	$ 2,754	0		(1)	$ 0	$ 746	$ 2,664		$ (655)
Beginning balance, Units (in shares) at Jun. 30, 2019	141,238,265				2,480,051	13,819,791	56,178,286		68,760,137
Units Outstanding [Roll Forward]
Units issued in public equity offerings (in shares)	1,635,669						1,635,669
Units issued in conversion of GP economic interest (in shares)	98,519,949				(2,480,051)				101,000,000
Ending balance, Units (in shares) at Sep. 30, 2019	241,393,883				0	13,819,791	57,813,955		169,760,137
Beginning Balance at Dec. 31, 2019	$ 2,834	0		(1)	$ 0	$ 746	$ 2,717		$ (628)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common units	2						2
Net income	697	10				29	168		490
Quarterly cash distributions to unitholders and General Partner	(627)					(28)	(153)		(446)
Transfer of equity interest	305	305
Proceeds from noncontrolling interest	3	3
Distributions to noncontrolling interest	(13)	(13)
Other distributions to Phillips 66	6								6
Ending Balance at Sep. 30, 2020	$ 3,207	305		(1)	$ 0	$ 747	$ 2,734		$ (578)
Beginning balance, Units (in shares) at Dec. 31, 2019	242,119,367				0	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 Sep. 30, 2020	242,159,937				0	13,819,791	58,580,009		169,760,137
Beginning Balance at Jun. 30, 2020	$ 3,213	305		(1)	$ 0	$ 746	$ 2,735		$ (572)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	216	10				10	50		146
Quarterly cash distributions to unitholders and General Partner	(209)					(9)	(51)		(149)
Proceeds from noncontrolling interest	3	3
Distributions to noncontrolling interest	(13)	(13)
Other distributions to Phillips 66	(3)								(3)
Ending Balance at Sep. 30, 2020	$ 3,207	$ 305		$ (1)	$ 0	$ 747	$ 2,734		$ (578)
Beginning balance, Units (in shares) at Jun. 30, 2020	242,159,937				0	13,819,791	58,580,009		169,760,137
Units Outstanding [Roll Forward]
Units issued in public equity offerings (in shares)	0						0
Ending balance, Units (in shares) at Sep. 30, 2020	242,159,937				0	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		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Stockholders' Equity [Abstract]
Cash distributions per common unit (in dollars per share)	$ 0.875	$ 0.855	$ 2.625	$ 2.535

Description of the Business

Description of the Business	9 Months Ended
Description of the Business	Sep. 30, 2020
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	9 Months Ended
Interim Financial Information	Sep. 30, 2020
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 2019 Annual Report on Form 10-K. The results of operations for the three and nine months ended September 30, 2020, are not necessarily indicative of the results to be expected for the full year. The Coronavirus Disease 2019 (COVID-19) pandemic continues to result in economic disruption 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 unknown. We continue to assess our long-lived assets and equity investments for impairment in this challenging business environment. Impairments may be required in the future if there is a further deterioration in our projected cash flows.

Operating Revenues

Operating Revenues	9 Months Ended
Operating Revenues	Sep. 30, 2020
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 Nine Months Ended 2020 2019 2020 2019 Pipelines $ 117 121 325 347 Terminals 36 41 112 120 Storage, processing and other revenues 112 108 336 368 Total operating revenues $ 265 270 773 835 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 Nine Months Ended 2020 2019 2020 2019 Lease revenues $ 209 217 622 688 Service revenues 56 53 151 147 Total operating revenues $ 265 270 773 835 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 September 30 December 31 Lease receivables $ 69 87 Service receivables 19 18 Total accounts receivable $ 88 105 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 September 30 December 31 Deferred lease revenues $ 41 41 Deferred service revenues 3 1 Total deferred revenues $ 44 42 Future Minimum Lease Payments from Customers At September 30, 2020, future minimum payments to be received under our lease agreements with customers were estimated to be: Millions Remainder of 2020 $ 178 2021 706 2022 694 2023 648 2024 526 Remaining years 1,389 Total future minimum lease payments from customers $ 4,141 Remaining Performance Obligations We typically have long-term service contracts with our customers, of which the original durations range from 5 to 15 years. The weighted-average remaining duration of these contracts is 10 years. These contracts include both fixed and variable transaction price components. At September 30, 2020, 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 2020 $ 39 2021 152 2022 151 2023 151 2024 132 Remaining years 756 Total future service revenues $ 1,381

Equity Investments

Equity Investments	9 Months Ended
Equity Investments	Sep. 30, 2020
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 September 30 December 31 Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline) 25.00 % $ 578 592 Bayou Bridge Pipeline, LLC (Bayou Bridge) 40.00 292 294 DCP Sand Hills Pipeline, LLC (Sand Hills) 33.34 586 595 DCP Southern Hills Pipeline, LLC (Southern Hills) 33.34 215 215 Explorer Pipeline Company (Explorer) 21.94 98 105 Gray Oak Pipeline, LLC 65.00 896 759 Liberty Pipeline LLC (Liberty) 50.00 239 — Paradigm Pipeline LLC (Paradigm) 50.00 141 143 Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal) 70.00 66 70 South Texas Gateway Terminal LLC (South Texas Gateway Terminal) 25.00 152 74 STACK Pipeline LLC (STACK) 50.00 110 114 Total equity investments $ 3,373 2,961 Earnings from our equity investments were as follows: Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Bakken Pipeline $ 37 58 124 167 Bayou Bridge 6 9 23 21 Sand Hills 33 39 111 113 Southern Hills 11 10 32 34 Explorer 6 12 17 26 Gray Oak Pipeline, LLC 30 (2) 49 (2) Liberty — — — — Paradigm 4 4 10 10 Phillips 66 Partners Terminal (1) 6 (2) 18 South Texas Gateway Terminal 2 — 2 — STACK 1 3 3 8 Total equity in earnings of affiliates $ 129 139 369 395 Dakota Access, LLC (Dakota Access) and Energy Transfer Crude Oil Company, LLC (ETCO) In March 2019, a wholly owned subsidiary of Dakota Access closed an offering of $2.5 billion aggregate principal amount of senior unsecured notes, consisting of: • $650 million aggregate principal amount of 3.625% Senior Notes due 2022. • $1.0 billion aggregate principal amount of 3.900% Senior Notes due 2024. • $850 million aggregate principal amount of 4.625% Senior Notes due 2029. 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 September 30, 2020, our share of the maximum potential equity contributions under the CECU was approximately $631 million. In March 2020, the trial court presiding over this litigation ordered the USACE to prepare an Environmental Impact Statement (EIS), and requested additional information to enable a decision on whether the Dakota Access Pipeline should be shut down while the EIS is being prepared. On July 6, 2020, the trial court ordered the Dakota Access Pipeline to be shut down and emptied of crude oil within 30 days, and that the pipeline should remain shut down pending the preparation of the EIS by the USACE, which the USACE has indicated is expected to take approximately 13 months. Dakota Access filed an appeal and a request for a stay of the order, which was granted. The case is now on an expedited appellate track and oral arguments regarding whether the pipeline easement is valid and whether the USACE must prepare an EIS are set for early November 2020, with a decision expected in late 2020 or early 2021. In addition to the proceedings in the appellate court, the trial court has been asked to issue an injunction to shut down the pipeline until the USACE completes the EIS, which could be ruled on as early as late December 2020 . If the pipeline is required to cease operations pending the preparation of the EIS, and should Dakota Access and ETCO not have sufficient funds to pay ongoing expenses, we also could be asked 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 Nine Months Ended 2020 2019 2020 2019 Revenues $ 196 258 623 748 Income before income taxes 121 189 401 527 Net income 121 189 401 527 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. I n 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, and the premium of $84 million previously paid by the co-venturer in 2019 was recharacterized from a long-term obligation to a gain in our consolidated statement of income. For the nine months ended September 30, 2020, the co-venturer contributed an aggregate of $64 million to the holding company to fund its portion of Gray Oak Pipeline, LLC’s cash calls. 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. In September 2020, Gray Oak Pipeline, LLC closed its offering of $1.4 billion aggregate principal amount of senior unsecured notes with maturities ranging from 2023 to 2027. These senior notes are not guaranteed by the Partnership or any of its co-venturers. Net proceeds from the offering were used to repay a third-party term loan of $1,379 million, and for general company purposes. Concurrent with the full repayment of the third-party term loan facility, the associated guarantee we issued through an equity contribution agreement was terminated. During its development phase, Gray Oak Pipeline, LLC was considered a variable interest entity (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-venturers jointly directed the activities of Gray Oak Pipeline, LLC that most significantly impact economic performance. The Gray Oak Pipeline commenced full operations in the second quarter of 2020 and ceased being a VIE. Liberty In February 2020, we entered into a Purchase and Sale Agreement with Phillips 66 PDI to acquire its 50% interest in the Liberty Pipeline joint venture for $75 million. The purchase price reflected the reimbursement of project costs incurred by Phillips 66 prior to the effective date of the transaction. The transaction was funded through a combination of cash on hand and our revolving credit facility, and closed on March 2, 2020. Liberty was formed to develop and construct the Liberty Pipeline system which, upon completion, will transport crude oil from the Rockies and Bakken production areas to Cushing, Oklahoma. On March 24, 2020, we and our co-venturer announced we are deferring the development and construction of the Liberty Pipeline system as a result of the current challenging business environment. Liberty is considered a VIE because it does not have sufficient equity at risk to fully fund the construction of all assets required for principal operations. We have determined we are not the primary beneficiary because we and our co-venturer jointly direct the activities of Liberty that most significantly impact economic performance. At September 30, 2020, our maximum exposure to loss was $239 million, which represented the aggregate book value of our equity investment in Liberty. At September 30, 2020, Phillips 66 had an outstanding guarantee of $13 million to vendors for our proportionate share of the payment of certain purchase obligations of Liberty.

Net Income Per Limited Partner

Net Income Per Limited Partner Unit	9 Months Ended
Net Income Per Limited Partner Unit	Sep. 30, 2020
Partners' Capital Notes [Abstract]
Net Income Per Limited Partner Unit	Note 5—Net Income Per Limited Partner Unit Net income per limited partner unit applicable to common units is computed by dividing the limited partners’ interest in net income by the weighted-average number of common units outstanding for the period. Prior to August 1, 2019, we had more than one class of participating securities and used the two-class method to calculate net income per unit applicable to the limited partners. The classes of participating securities prior to August 1, 2019, included common units, general partner units and incentive distribution rights (IDRs). Effective August 1, 2019, common units are the only participating securities. For the three and nine months ended September 30, 2020 and 2019, our preferred units are potentially dilutive securities and 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 our partnership agreement, after giving effect to priority income allocations to the holders of the preferred units. First, earnings are allocated based on actual cash distributions declared to our unitholders. To the extent net income exceeds or is less than cash distributions declared, this difference is allocated based on the unitholders’ respective ownership percentages, after consideration of any priority allocations of earnings. For the diluted net income 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 which would not have been paid after conversion. Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Net income attributable to the Partnership $ 206 237 687 668 Less: General partners’ distributions declared (including IDRs)* — — — 139 Limited partners’ distributions declared on preferred units* 10 9 29 28 Limited partners’ distributions declared on common units* 200 197 599 409 Distributions less than (more than) net income attributable to the Partnership $ (4) 31 59 92 Distributions declared are attributable to the indicated periods. Limited Limited Total Three Months Ended September 30, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 200 10 210 Distributions more than net income attributable to the Partnership (4) — (4) Net income attributable to the Partnership (basic) 196 10 206 Dilutive effect of preferred units 10 Net income attributable to the Partnership (diluted) $ 206 Weighted-average units outstanding—basic 228,340,146 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,159,937 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 0.86 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 0.85 Limited Limited Total Three Months Ended September 30, 2019 Net income attributable to the Partnership (millions) : Distributions declared $ 197 9 206 Distributions less than net income attributable to the Partnership 31 — 31 Net income attributable to the Partnership (basic) 228 9 237 Dilutive effect of preferred units 9 Net income attributable to the Partnership (diluted) $ 237 Weighted-average units outstanding—basic 192,273,672 Dilutive effect of preferred units 13,819,792 Weighted-average units outstanding—diluted 206,093,464 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 1.18 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 1.15 Limited Limited Total Nine Months Ended September 30, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 599 29 628 Distributions less than net income attributable to the Partnership 59 — 59 Net income attributable to the Partnership (basic) 658 29 687 Dilutive effect of preferred units 29 Net income attributable to the Partnership (diluted) $ 687 Weighted-average units outstanding—basic 228,330,885 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,150,676 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 2.88 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 2.84 Limited General Limited Total Nine Months Ended September 30, 2019 Net income attributable to the Partnership (millions) : Distributions declared $ 409 139 28 576 Distributions less than net income attributable to the Partnership 91 1 — 92 Net income attributable to the Partnership (basic) 500 140 28 668 Dilutive effect of preferred units 23 Net income attributable to the Partnership (diluted) $ 523 Weighted-average units outstanding—basic 147,367,681 Dilutive effect of preferred units* 13,819,791 Weighted-average units outstanding—diluted 161,187,472 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 3.39 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 3.25 *The dilutive effect of preferred units assumes the reallocation of net income attributable to the partnership to the limited and general partners, including a reallocation associated with IDRs, pursuant to the available cash formula in the partnership agreement.

Properties, Plants and Equipmen

Properties, Plants and Equipment	9 Months Ended
Properties, Plants and Equipment	Sep. 30, 2020
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 September 30 December 31 Land $ 19 19 Buildings and improvements 95 94 Pipelines and related assets * 1,522 1,424 Terminals and related assets * 840 741 Rail racks and related assets * 137 137 Processing and related assets * 1,058 1,041 Caverns and related assets * 742 585 Construction-in-progress 312 367 Gross PP&E 4,725 4,408 Accumulated depreciation (1,150) (1,059) Net PP&E $ 3,575 3,349 *Assets for which we are the lessor.

Debt

Debt	9 Months Ended
Debt	Sep. 30, 2020
Debt Disclosure [Abstract]
Debt	Note 7—Debt Millions of Dollars September 30 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 2020 and April 2021 at 0.535% and 1.85% at September 30, 2020, and December 31, 2019, respectively 50 75 Revolving credit facility borrowings due October 2020 at 1.401% 290 — Debt at face value 3,815 3,550 Net unamortized discounts and debt issuance costs (32) (34) Total debt 3,783 3,516 Short-term debt (340) (25) Long-term debt $ 3,443 3,491 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 $3,567 million and $3,650 million at September 30, 2020, and December 31, 2019, respectively. The fair value of our floating-rate debt approximated carrying value of $340 million and $75 million at September 30, 2020, and December 31, 2019, respectively. At September 30, 2020, borrowings of $290 million were outstanding and $3 million in letters of credit had been drawn under our $750 million revolving credit facility.

Contingencies

Contingencies	9 Months Ended
Contingencies	Sep. 30, 2020
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 less than certain. 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. 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 September 30, 2020, and December 31, 2019, 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	9 Months Ended
Equity	Sep. 30, 2020
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 did not issue any common units under the current ATM program during the three months ended September 30, 2020. For the nine months ended September 30, 2020, on a settlement date basis, we issued an aggregate of 40,570 common units, generating net proceeds of $2 million. For the three and nine months ended September 30, 2019, we issued an aggregate of 1,635,669 and 2,470,037 common units, respectively, generating net proceeds of $91 million and $133 million, respectively. Since inception in June 2016 through September 30, 2020, we issued an aggregate of 9,487,055 common units under our ATM programs, and generated net proceeds of $494 million, after broker commissions of $5 million and other costs of $3 million. The net proceeds from sales under the ATM programs are used for general partnership purposes, which may include debt repayment, acquisitions, capital expenditures and additions to working capital. Restructuring Transaction On August 1, 2019, we closed on the transactions contemplated by the Partnership Interests Restructuring Agreement, dated July 24, 2019, entered into with our General Partner. Pursuant to this agreement, all of the outstanding IDRs held by our General Partner were eliminated and its approximately 2% general partner interest in us was converted into a non-economic general partner interest; both in exchange for an aggregate of 101 million common units issued to Phillips 66 PDI. Because these transactions were between entities under common control, the common units issued to Phillips 66 PDI were not assigned any value; rather, our General Partner’s negative equity balance of $1.4 billion at August 1, 2019, was transferred to Phillips 66’s limited partner equity account.

Related Party Transactions

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2020
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 Nine Months Ended 2020 2019 2020 2019 Operating and maintenance expenses $ 46 48 136 203 General and administrative expenses 15 14 46 47 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 September 30 December 31 Prepaid expenses and other current assets $ 4 7 Other assets 48 44 Deferred revenues 22 16 Other current liabilities 1 1 Other liabilities 66 70 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. In September 2020, concurrent with the full repayment of a third-party term loan facility by Gray Oak Pipeline, LLC, the associated guarantee we issued through an equity contribution agreement was terminated. See Note 4—Equity Investments, for additional information.

Cash Flow Information

Cash Flow Information	9 Months Ended
Cash Flow Information	Sep. 30, 2020
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 Nine Months Ended 2020 2019 Cash capital expenditures and investments $ 796 924 Change in capital expenditure accruals (1) (17) Total capital expenditures and investments $ 795 907

Net Income Per Limited Partne_2

Net Income Per Limited Partner Unit (Policies)	9 Months Ended
Net Income Per Limited Partner Unit (Policies)	Sep. 30, 2020
Partners' Capital Notes [Abstract]
Net Income Per Limited Partner Unit	Net income per limited partner unit applicable to common units is computed by dividing the limited partners’ interest in net income by the weighted-average number of common units outstanding for the period. Prior to August 1, 2019, we had more than one class of participating securities and used the two-class method to calculate net income per unit applicable to the limited partners. The classes of participating securities prior to August 1, 2019, included common units, general partner units and incentive distribution rights (IDRs). Effective August 1, 2019, common units are the only participating securities. For the three and nine months ended September 30, 2020 and 2019, our preferred units are potentially dilutive securities and were dilutive to net income per limited partner unit.

Operating Revenues (Tables)

Operating Revenues (Tables)	9 Months Ended
Operating Revenues (Tables)	Sep. 30, 2020
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 Nine Months Ended 2020 2019 2020 2019 Pipelines $ 117 121 325 347 Terminals 36 41 112 120 Storage, processing and other revenues 112 108 336 368 Total operating revenues $ 265 270 773 835 Total operating revenues disaggregated by lease and service revenues were as follows: Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Lease revenues $ 209 217 622 688 Service revenues 56 53 151 147 Total operating revenues $ 265 270 773 835
Accounts Receivable	Total accounts receivable by revenue type was as follows: Millions of Dollars September 30 December 31 Lease receivables $ 69 87 Service receivables 19 18 Total accounts receivable $ 88 105
Deferred Revenues	Total deferred revenues under our lease and service agreements were as follows: Millions of Dollars September 30 December 31 Deferred lease revenues $ 41 41 Deferred service revenues 3 1 Total deferred revenues $ 44 42
Schedule of Future Minimum Payments Receivable	At September 30, 2020, future minimum payments to be received under our lease agreements with customers were estimated to be: Millions Remainder of 2020 $ 178 2021 706 2022 694 2023 648 2024 526 Remaining years 1,389 Total future minimum lease payments from customers $ 4,141
Expected Timing of Satisfaction	At September 30, 2020, 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 2020 $ 39 2021 152 2022 151 2023 151 2024 132 Remaining years 756 Total future service revenues $ 1,381

Equity Investments (Tables)

Equity Investments (Tables)	9 Months Ended
Equity Investments (Tables)	Sep. 30, 2020
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 September 30 December 31 Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline) 25.00 % $ 578 592 Bayou Bridge Pipeline, LLC (Bayou Bridge) 40.00 292 294 DCP Sand Hills Pipeline, LLC (Sand Hills) 33.34 586 595 DCP Southern Hills Pipeline, LLC (Southern Hills) 33.34 215 215 Explorer Pipeline Company (Explorer) 21.94 98 105 Gray Oak Pipeline, LLC 65.00 896 759 Liberty Pipeline LLC (Liberty) 50.00 239 — Paradigm Pipeline LLC (Paradigm) 50.00 141 143 Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal) 70.00 66 70 South Texas Gateway Terminal LLC (South Texas Gateway Terminal) 25.00 152 74 STACK Pipeline LLC (STACK) 50.00 110 114 Total equity investments $ 3,373 2,961 Earnings from our equity investments were as follows: Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Bakken Pipeline $ 37 58 124 167 Bayou Bridge 6 9 23 21 Sand Hills 33 39 111 113 Southern Hills 11 10 32 34 Explorer 6 12 17 26 Gray Oak Pipeline, LLC 30 (2) 49 (2) Liberty — — — — Paradigm 4 4 10 10 Phillips 66 Partners Terminal (1) 6 (2) 18 South Texas Gateway Terminal 2 — 2 — STACK 1 3 3 8 Total equity in earnings of affiliates $ 129 139 369 395 Summarized financial information for 100% of Dakota Access is as follows: Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Revenues $ 196 258 623 748 Income before income taxes 121 189 401 527 Net income 121 189 401 527

Net Income Per Limited Partne_3

Net Income Per Limited Partner Unit (Tables)	9 Months Ended
Net Income Per Limited Partner Unit (Tables)	Sep. 30, 2020
Partners' Capital Notes [Abstract]
Schedule of Distributions Declared, Partners Interest in Partnership Net Income and Net Income per Unit by Class	Net income earned by the Partnership is allocated between the classes of participating securities in accordance with our partnership agreement, after giving effect to priority income allocations to the holders of the preferred units. First, earnings are allocated based on actual cash distributions declared to our unitholders. To the extent net income exceeds or is less than cash distributions declared, this difference is allocated based on the unitholders’ respective ownership percentages, after consideration of any priority allocations of earnings. For the diluted net income 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 which would not have been paid after conversion. Millions of Dollars Three Months Ended Nine Months Ended 2020 2019 2020 2019 Net income attributable to the Partnership $ 206 237 687 668 Less: General partners’ distributions declared (including IDRs)* — — — 139 Limited partners’ distributions declared on preferred units* 10 9 29 28 Limited partners’ distributions declared on common units* 200 197 599 409 Distributions less than (more than) net income attributable to the Partnership $ (4) 31 59 92 Distributions declared are attributable to the indicated periods. Limited Limited Total Three Months Ended September 30, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 200 10 210 Distributions more than net income attributable to the Partnership (4) — (4) Net income attributable to the Partnership (basic) 196 10 206 Dilutive effect of preferred units 10 Net income attributable to the Partnership (diluted) $ 206 Weighted-average units outstanding—basic 228,340,146 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,159,937 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 0.86 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 0.85 Limited Limited Total Three Months Ended September 30, 2019 Net income attributable to the Partnership (millions) : Distributions declared $ 197 9 206 Distributions less than net income attributable to the Partnership 31 — 31 Net income attributable to the Partnership (basic) 228 9 237 Dilutive effect of preferred units 9 Net income attributable to the Partnership (diluted) $ 237 Weighted-average units outstanding—basic 192,273,672 Dilutive effect of preferred units 13,819,792 Weighted-average units outstanding—diluted 206,093,464 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 1.18 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 1.15 Limited Limited Total Nine Months Ended September 30, 2020 Net income attributable to the Partnership (millions) : Distributions declared $ 599 29 628 Distributions less than net income attributable to the Partnership 59 — 59 Net income attributable to the Partnership (basic) 658 29 687 Dilutive effect of preferred units 29 Net income attributable to the Partnership (diluted) $ 687 Weighted-average units outstanding—basic 228,330,885 Dilutive effect of preferred units 13,819,791 Weighted-average units outstanding—diluted 242,150,676 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 2.88 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 2.84 Limited General Limited Total Nine Months Ended September 30, 2019 Net income attributable to the Partnership (millions) : Distributions declared $ 409 139 28 576 Distributions less than net income attributable to the Partnership 91 1 — 92 Net income attributable to the Partnership (basic) 500 140 28 668 Dilutive effect of preferred units 23 Net income attributable to the Partnership (diluted) $ 523 Weighted-average units outstanding—basic 147,367,681 Dilutive effect of preferred units* 13,819,791 Weighted-average units outstanding—diluted 161,187,472 Net income attributable to the Partnership per limited partner unit—basic (dollars) $ 3.39 Net income attributable to the Partnership per limited partner unit—diluted (dollars) 3.25 *The dilutive effect of preferred units assumes the reallocation of net income attributable to the partnership to the limited and general partners, including a reallocation associated with IDRs, pursuant to the available cash formula in the partnership agreement.

Properties, Plants and Equipm_2

Properties, Plants and Equipment (Tables)	9 Months Ended
Properties, Plants and Equipment (Tables)	Sep. 30, 2020
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 September 30 December 31 Land $ 19 19 Buildings and improvements 95 94 Pipelines and related assets * 1,522 1,424 Terminals and related assets * 840 741 Rail racks and related assets * 137 137 Processing and related assets * 1,058 1,041 Caverns and related assets * 742 585 Construction-in-progress 312 367 Gross PP&E 4,725 4,408 Accumulated depreciation (1,150) (1,059) Net PP&E $ 3,575 3,349 *Assets for which we are the lessor.

Debt (Tables)

Debt (Tables)	9 Months Ended
Debt (Tables)	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Debt	Millions of Dollars September 30 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 2020 and April 2021 at 0.535% and 1.85% at September 30, 2020, and December 31, 2019, respectively 50 75 Revolving credit facility borrowings due October 2020 at 1.401% 290 — Debt at face value 3,815 3,550 Net unamortized discounts and debt issuance costs (32) (34) Total debt 3,783 3,516 Short-term debt (340) (25) Long-term debt $ 3,443 3,491

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
Related Party Transactions (Tables)	Sep. 30, 2020
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 Nine Months Ended 2020 2019 2020 2019 Operating and maintenance expenses $ 46 48 136 203 General and administrative expenses 15 14 46 47 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 September 30 December 31 Prepaid expenses and other current assets $ 4 7 Other assets 48 44 Deferred revenues 22 16 Other current liabilities 1 1 Other liabilities 66 70

Cash Flow Information (Tables)

Cash Flow Information (Tables)	9 Months Ended
Cash Flow Information (Tables)	Sep. 30, 2020
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 Nine Months Ended 2020 2019 Cash capital expenditures and investments $ 796 924 Change in capital expenditure accruals (1) (17) Total capital expenditures and investments $ 795 907

Description of the Business (De

Description of the Business (Details)	9 Months Ended
Description of the Business (Details)	Sep. 30, 2020segmentrefinery
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

Operating Revenues (Revenues Di

Operating Revenues (Revenues Disaggregated) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	$ 265	$ 270	$ 773	$ 835
Pipelines
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	117	121	325	347
Terminals
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	36	41	112	120
Storage, processing and other revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	$ 112	$ 108	$ 336	$ 368

Operating Revenues (Operating R

Operating Revenues (Operating Revenues) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	$ 265	$ 270	$ 773	$ 835
Lease revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	209	217	622	688
Service revenues
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Operating revenues	$ 56	$ 53	$ 151	$ 147

Operating Revenues (Accounts Re

Operating Revenues (Accounts Receivable) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Total accounts receivable	$ 88	$ 105
Lease receivables
Revenue from External Customer [Line Items]
Total accounts receivable	69	87
Service receivables
Revenue from External Customer [Line Items]
Total accounts receivable	$ 19	$ 18

Operating Revenues (Deferred Re

Operating Revenues (Deferred Revenue) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Total deferred revenues	$ 44	$ 42
Lease revenues
Revenue from External Customer [Line Items]
Total deferred revenues	41	41
Service revenues
Revenue from External Customer [Line Items]
Total deferred revenues	$ 3	$ 1

Operating Revenues (Schedule of

Operating Revenues (Schedule of Future Minimum Operating Lease Income) (Details) $ in Millions	Sep. 30, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Remainder of 2020	$ 178
2021	706
2022	694
2023	648
2024	526
Remaining years	1,389
Total future minimum lease payments from customers	$ 4,141

Operating Revenues (Narrative)

Operating Revenues (Narrative) (Details)	9 Months Ended
Operating Revenues (Narrative) (Details)	Sep. 30, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer contracts, average remaining duration	10 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 (Performance

Operating Revenues (Performance Obligations) (Details) $ in Millions	Sep. 30, 2020USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 1,381
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 39
Revenue, remaining performance obligation, expected timing of satisfaction, period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, amount	$ 152
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
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	$ 151
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	$ 151
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	$ 132
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	$ 756
Revenue, remaining performance obligation, expected timing of satisfaction, period

Equity Investments (Schedule of

Equity Investments (Schedule of Carrying Value Equity Investments) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Carrying Value	$ 3,373	$ 2,961
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	$ 578	592
Bayou Bridge Pipeline, LLC (Bayou Bridge)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	40.00%
Carrying Value	$ 292	294
DCP Sand Hills Pipeline, LLC (Sand Hills)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	33.34%
Carrying Value	$ 586	595
DCP Southern Hills Pipeline, LLC (Southern Hills)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	33.34%
Carrying Value	$ 215	215
Explorer Pipeline Company (Explorer)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	21.94%
Carrying Value	$ 98	105
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	65.00%
Carrying Value	$ 896	759
Liberty Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value		0
Paradigm Pipeline LLC (Paradigm)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value	$ 141	143
Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	70.00%
Carrying Value	$ 66	70
South Texas Gateway Terminal LLC (South Texas Gateway Terminal)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	25.00%
Carrying Value	$ 152	74
STACK Pipeline LLC (STACK)
Schedule of Equity Method Investments [Line Items]
Percentage Ownership	50.00%
Carrying Value	$ 110	$ 114

Equity Investments (Schedule _2

Equity Investments (Schedule of Equity Investment Earnings (Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	$ 129	$ 139	$ 369	$ 395
Dakota Access, LLC and Energy Transfer Crude Oil Company, LLC (Bakken Pipeline)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	37	58	124	167
Bayou Bridge Pipeline, LLC (Bayou Bridge)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	6	9	23	21
DCP Sand Hills Pipeline, LLC (Sand Hills)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	33	39	111	113
DCP Southern Hills Pipeline, LLC (Southern Hills)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	11	10	32	34
Explorer Pipeline Company (Explorer)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	6	12	17	26
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	30	(2)	49	(2)
Liberty Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	0	0	0	0
Paradigm Pipeline LLC (Paradigm)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	4	4	10	10
Phillips 66 Partners Terminal LLC (Phillips 66 Partners Terminal)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	(1)	6	(2)	18
South Texas Gateway Terminal LLC (South Texas Gateway Terminal)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	2	0	2	0
STACK Pipeline LLC (STACK)
Schedule of Equity Method Investments [Line Items]
Total equity in earnings of affiliates	$ 1	$ 3	$ 3	$ 8

Equity Investments (Narrative)

Equity Investments (Narrative) (Details) - USD ($)

Sep. 30, 2020

Sep. 15, 2020

Jul. 06, 2020

Feb. 29, 2020

Sep. 30, 2020

Jun. 30, 2020

Sep. 30, 2019

Sep. 30, 2020

Sep. 30, 2019

Mar. 31, 2019

Feb. 28, 2019

Dec. 31, 2018

Schedule of Equity Method Investments [Line Items]

Gain from equity interest transfer

$ 0

$ 84,000,000

$ 0

Repayments of debt

25,000,000

$ 985,000,000

Gray Oak Pipeline, LLC

Schedule of Equity Method Investments [Line Items]

Repayments of debt

$ 1,379,000,000

Gray Oak Pipeline, LLC | Senior Notes

Schedule of Equity Method Investments [Line Items]

Debt instrument, face amount

$ 1,400,000,000

Dakota Access, LLC

Schedule of Equity Method Investments [Line Items]

Estimated period of time to prepare Environmental Impact Statement

13 months

Dakota Access, LLC | Senior Notes

Schedule of Equity Method Investments [Line Items]

Debt instrument, face amount

$ 2,500,000,000

Dakota Access, LLC | Senior Notes | Senior Notes Due 2022

Schedule of Equity Method Investments [Line Items]

Debt instrument, face amount

$ 650,000,000

Interest rate, stated percentage

3.625%

Dakota Access, LLC | Senior Notes | Senior Notes Due 2024

Schedule of Equity Method Investments [Line Items]

Debt instrument, face amount

$ 1,000,000,000

Interest rate, stated percentage

3.90%

Dakota Access, LLC | Senior Notes | Senior Notes Due 2029

Schedule of Equity Method Investments [Line Items]

Debt instrument, face amount

$ 850,000,000

Interest rate, stated percentage

4.625%

Dakota Access and ETCO

Schedule of Equity Method Investments [Line Items]

Scheduled annual interest payments

$ 25,000,000

Common Control Transaction | Phillips 66 | Phillips 66 PDI | Liberty Pipeline, LLC

Schedule of Equity Method Investments [Line Items]

Controlling interest acquired, percentage

50.00%

Business combination, consideration transferred

$ 75,000,000

Liberty Pipeline, LLC

Schedule of Equity Method Investments [Line Items]

Ownership interest acquired, percentage

50.00%

VIE, reporting entity involvement, maximum exposure

$ 239,000,000

Guarantor obligations, current carrying value

$ 13,000,000

Gray Oak Pipeline, LLC

Schedule of Equity Method Investments [Line Items]

Ownership interest acquired, percentage

65.00%

Gain from equity interest transfer

$ 84,000,000

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 Pipeline, LLC | Third Party

Schedule of Equity Method Investments [Line Items]

Amount contributed to fund cash calls

$ 64,000,000

Gray Oak Holdings LLC | Third Party

Schedule of Equity Method Investments [Line Items]

Percentage of ownership

35.00%

Dakota Access and ETCO

Schedule of Equity Method Investments [Line Items]

Maximum exposure, undiscounted

$ 631,000,000

Equity Investments (Schedule _3

Equity Investments (Schedule of Dakota Access) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Schedule of Equity Method Investments [Line Items]
Revenues	$ 265	$ 270	$ 773	$ 835
Income before income taxes	217	238	699	671
Net income	206	237	687	668
Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Revenues	196	258	623	748
Income before income taxes	121	189	401	527
Net income	$ 121	$ 189	$ 401	$ 527

Net Income Per Limited Partne_4

Net Income Per Limited Partner Unit (Narrative) (Details) $ / shares in Units, $ in Millions	Oct. 20, 2020USD ($)$ / shares	Sep. 30, 2020
Subsequent Event [Line Items]
Conversion ratio of preferred units to common units		1
Common Units \| Cash Distribution \| Subsequent Event
Subsequent Event [Line Items]
Quarterly cash distribution declared per limited partner unit (in dollars per share) \| $ / shares	$ 0.875
Distribution made to limited partner, cash distributions declared \| $	$ 200

Net Income Per Limited Partne_5

Net Income Per Limited Partner Unit (Schedule of Earnings Per unit of our Limited Partners) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Limited Partners' Capital Account [Line Items]
Net income attributable to the Partnership	$ 206	$ 237	$ 687	$ 668
Less:
Distributions declared	210	206	628	576
Distributions less than (more than) net income attributable to the Partnership	(4)	31	59	92
General Partner
Limited Partners' Capital Account [Line Items]
Net income attributable to the Partnership				140
Less:
Distributions declared	0	0	0	139
Preferred Units \| Limited Partner
Limited Partners' Capital Account [Line Items]
Net income attributable to the Partnership	10	9	29	28
Less:
Distributions declared	10	9	29	28
Common Units \| Limited Partner
Limited Partners' Capital Account [Line Items]
Net income attributable to the Partnership	196	228	658	500
Less:
Distributions declared	$ 200	$ 197	$ 599	$ 409

Net Income Per Limited Partne_6

Net Income Per Limited Partner Unit (Schedule of Net Income By Class of Participating Securities) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Limited Partners' Capital Account [Line Items]
Distributions declared	$ 210	$ 206	$ 628	$ 576
Distributions more than net income attributable to the Partnership	(4)	31	59	92
Net income attributable to the Partnership	$ 206	$ 237	$ 687	$ 668
Limited Partners’ Common Units
Limited Partners' Capital Account [Line Items]
Weighted-average units outstanding—basic (in shares)	228,340,146	192,273,672	228,330,885	147,367,681
Dilutive effect of preferred units (in shares)	13,819,791	13,819,792	13,819,791	13,819,791
Weighted-average units outstanding—diluted (in shares)	242,159,937	206,093,464	242,150,676	161,187,472
Net income attributable to the Partnership per limited partner unit—basic (in dollars per share)	$ 0.86	$ 1.18	$ 2.88	$ 3.39
Net income attributable to the Partnership per limited partner unit—diluted (in dollars per share)	$ 0.85	$ 1.15	$ 2.84	$ 3.25
Limited Partner \| Limited Partners’ Common Units
Limited Partners' Capital Account [Line Items]
Distributions declared	$ 200	$ 197	$ 599	$ 409
Distributions more than net income attributable to the Partnership	(4)	31	59	91
Net income attributable to the Partnership	196	228	658	500
Dilutive effect of preferred units	10	9	29	23
Net income attributable to the Partnership (diluted)	206	237	687	523
Limited Partner \| Limited Partners’ Preferred Units
Limited Partners' Capital Account [Line Items]
Distributions declared	10	9	29	28
Distributions more than net income attributable to the Partnership	0	0	0	0
Net income attributable to the Partnership	10	9	29	28
General Partner (including IDRs)
Limited Partners' Capital Account [Line Items]
Distributions declared	$ 0	$ 0	$ 0	139
Distributions more than net income attributable to the Partnership				1
Net income attributable to the Partnership				$ 140

Properties, Plants and Equipm_3

Properties, Plants and Equipment (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 4,725	$ 4,408
Accumulated depreciation	(1,150)	(1,059)
Net PP&E	3,575	3,349
Land
Property, Plant and Equipment [Line Items]
Gross PP&E	19	19
Buildings and improvements
Property, Plant and Equipment [Line Items]
Gross PP&E	95	94
Pipelines and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	1,522	1,424
Terminals and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	840	741
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	1,058	1,041
Caverns and related assets
Property, Plant and Equipment [Line Items]
Gross PP&E	742	585
Construction-in-progress
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 312	$ 367

Debt (Summary of Long-Term Debt

Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt at face value	$ 3,815	$ 3,550
Net unamortized discounts and debt issuance costs	(32)	(34)
Total debt	3,783	3,516
Short-term debt	(340)	(25)
Long-term debt	3,443	3,491
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 290	0
Interest rate, stated percentage	1.401%
Tax-exempt bonds due April 2020 and April 2021 at 0.535% and 1.85% at September 30, 2020, and December 31, 2019, respectively
Debt Instrument [Line Items]
Long-term debt, gross	$ 50	$ 75
Short-term debt	$ (50)
Interest rate, stated percentage	0.535%	1.85%
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)	Apr. 01, 2020USD ($)tranche	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Line of credit facility, outstanding		$ 290,000,000
Letters of credit outstanding, amount		3,000,000
Repayments of debt		25,000,000	$ 985,000,000
Short-term debt		340,000,000		$ 25,000,000
Tax-Exempt Bonds
Debt Instrument [Line Items]
Repayments of debt	$ 25,000,000
Number of tranches remaining \| tranche	2
Short-term debt		50,000,000
Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		750,000,000
Fair Value, Inputs, Level 2 \| Tax-Exempt Bonds
Debt Instrument [Line Items]
Debt instrument, fair value disclosure		340,000,000		75,000,000
Fair Value, Inputs, Level 2 \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, fair value disclosure		$ 3,567,000,000		$ 3,650,000,000

Equity (Details)

Equity (Details)	Aug. 01, 2019USD ($)shares	Sep. 30, 2020offeringshares	Sep. 30, 2019USD ($)shares	Sep. 30, 2020USD ($)offeringshares	Sep. 30, 2019USD ($)shares	Sep. 30, 2020USD ($)offeringshares
Limited Partners' Capital Account [Line Items]
Number of common units issued in public offering (in shares) \| shares		0	1,635,669	40,570	2,470,037
General Partner Interest To Be Converted Into Non-Economic General Partner Interest
Limited Partners' Capital Account [Line Items]
General partner interest, percent	2.00%
Common Units
Limited Partners' Capital Account [Line Items]
Shares, issued (in shares) \| shares	101,000,000
General partners equity balance	$ 1,400,000,000
At The Market Offering Program
Limited Partners' Capital Account [Line Items]
Aggregate authorized amount				$ 750,000,000
At The Market Offering Program \| Common Units
Limited Partners' Capital Account [Line Items]
Number of continuous offerings \| offering		3		3		3
Authorized amount per program				$ 250,000,000
Number of common units issued in public offering (in shares) \| shares		0	1,635,669	40,570	2,470,037	9,487,055
Issuance of common units			$ 91,000,000	$ 2,000,000	$ 133,000,000	$ 494,000,000
Brokers commissions						5,000,000
Other costs						$ 3,000,000

Related Party Transactions (Nar

Related Party Transactions (Narrative) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)
Phillips 66 \| Phillips 66 \| Amended Omnibus Agreement
Related Party Transaction [Line Items]
Monthly operational and administrative support fee	$ 8

Related Party Transactions (Sum

Related Party Transactions (Summary of Related Party Transactions) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Related Party Transactions [Abstract]
Operating and maintenance expenses	$ 46	$ 48	$ 136	$ 203
General and administrative expenses	$ 15	$ 14	$ 46	$ 47

Related Party Transactions (Oth

Related Party Transactions (Other Related Party Balances) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	$ 7	$ 10
Other assets	50	52
Deferred revenues	22	16
Other current liabilities	3	3
Other liabilities	91	94
Phillips 66
Related Party Transaction [Line Items]
Prepaid expenses and other current assets	4	7
Other assets	48	44
Deferred revenues	22	16
Other current liabilities	1	1
Other liabilities	$ 66	$ 70

Cash Flow Information (Details)

Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
Cash Flow Information (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Supplemental Cash Flow Information [Abstract]
Cash capital expenditures and investments	$ 796	$ 924
Change in capital expenditure accruals	(1)	(17)
Total capital expenditures and investments	$ 795	$ 907