Phillips 66 (PSX) 10-Q 29 Oct 21 2021 Q3 Quarterly report Financial data

Cover

Cover	9 Months Ended
	Sep. 30, 2021shares
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-35349
Entity Registrant Name	Phillips 66
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-3779385
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	281
Local Phone Number	293-6600
Title of 12(b) Security	Common Stock, $0.01 Par Value
Trading Symbol	PSX
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	438,100,273
Entity Central Index Key	0001534701
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Statement of Opera

Consolidated Statement of Operations - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues and Other Income
Sales and other operating revenues	$ 30,243	$ 15,929	$ 78,872	$ 47,720
Equity in earnings of affiliates	982	349	2,097	871
Net gain on dispositions	9	1	11	87
Other income	238	20	304	48
Total Revenues and Other Income	31,472	16,299	81,284	48,726
Costs and Expenses
Purchased crude oil and products	27,529	14,509	72,812	42,557
Operating expenses	1,166	1,016	3,721	3,383
Selling, general and administrative expenses	424	384	1,265	1,112
Depreciation and amortization	361	352	1,081	1,037
Impairments	1,298	1,140	1,496	4,146
Taxes other than income taxes	85	106	343	377
Accretion on discounted liabilities	6	6	18	17
Interest and debt expense	151	132	440	360
Foreign currency transaction (gains) losses	4	4	(5)	10
Total Costs and Expenses	31,024	17,649	81,171	52,999
Income (loss) before income taxes	448	(1,350)	113	(4,273)
Income tax benefit	(40)	(624)	(110)	(1,053)
Net Income (Loss)	488	(726)	223	(3,220)
Less: net income attributable to noncontrolling interests	86	73	179	216
Net Income (Loss) Attributable to Phillips 66	$ 402	$ (799)	$ 44	$ (3,436)
Net Income (Loss) Attributable to Phillips 66 Per Share of Common Stock (dollars)
Basic (in usd per share)	$ 0.91	$ (1.82)	$ 0.08	$ (7.83)
Diluted (in usd per share)	$ 0.91	$ (1.82)	$ 0.08	$ (7.83)
Weighted-Average Common Shares Outstanding (thousands)
Basic (in shares)	440,193	438,916	439,880	439,670
Diluted (in shares)	440,368	438,916	440,259	439,670

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 488	$ (726)	$ 223	$ (3,220)
Defined benefit plans
Net actuarial gain (loss) arising during the period	0	0	210	(300)
Amortization of net actuarial loss, prior service credit and settlements	36	34	105	112
Plans sponsored by equity affiliates	4	4	33	9
Income taxes on defined benefit plans	(8)	(10)	(82)	44
Defined benefit plans, net of income taxes	32	28	266	(135)
Foreign currency translation adjustments	(74)	155	(70)	(41)
Income taxes on foreign currency translation adjustments	2	(4)	2	(3)
Foreign currency translation adjustments, net of income taxes	(72)	151	(68)	(44)
Cash flow hedges	0	2	3	(7)
Income taxes on hedging activities	0	0	(1)	2
Hedging activities, net of income taxes	0	2	2	(5)
Other Comprehensive Income (Loss), Net of Income Taxes	(40)	181	200	(184)
Comprehensive Income (Loss)	448	(545)	423	(3,404)
Less: comprehensive income attributable to noncontrolling interests	86	73	179	216
Comprehensive Income (Loss) Attributable to Phillips 66	$ 362	$ (618)	$ 244	$ (3,620)

Consolidated Balance Sheet

Consolidated Balance Sheet - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 2,897	$ 2,514
Accounts and notes receivable (net of allowances of $36 million in 2021 and $37 million in 2020)	6,527	5,688
Accounts and notes receivable—related parties	1,479	834
Inventories	4,400	3,893
Prepaid expenses and other current assets	716	347
Total Current Assets	16,019	13,276
Investments and long-term receivables	14,059	13,624
Net properties, plants and equipment	22,377	23,716
Goodwill	1,425	1,425
Intangibles	822	843
Other assets	1,705	1,837
Total Assets	56,407	54,721
Liabilities
Accounts payable	8,203	5,171
Accounts payable—related parties	1,012	378
Short-term debt	1,489	987
Accrued income and other taxes	1,287	1,351
Employee benefit obligations	464	573
Other accruals	1,466	1,058
Total Current Liabilities	13,921	9,518
Long-term debt	13,421	14,906
Asset retirement obligations and accrued environmental costs	680	657
Deferred income taxes	5,434	5,644
Employee benefit obligations	1,123	1,341
Other liabilities and deferred credits	1,231	1,132
Total Liabilities	35,810	33,198
Equity
Common stock (2,500,000,000 shares authorized at $0.01 par value) Issued (2021— shares; 2020—648,643,223 shares) Par value	6	6
Capital in excess of par	20,488	20,383
Treasury stock (at cost: 2021 and 2020—211,771,827 shares)	(17,116)	(17,116)
Retained earnings	15,350	16,500
Accumulated other comprehensive loss	(589)	(789)
Total Stockholders’ Equity	18,139	18,984
Noncontrolling interests	2,458	2,539
Total Equity	20,597	21,523
Total Liabilities and Equity	$ 56,407	$ 54,721

Consolidated Balance Sheet (Par

Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for credit losses	$ 36	$ 37
Common stock authorized (in shares)	2,500,000,000	2,500,000,000
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock issued (in shares)	649,872,100	648,643,223
Treasury stock (in shares)	211,771,827	211,771,827

Consolidated Statement of Cash

Consolidated Statement of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash Flows From Operating Activities
Net income (loss)	$ 223	$ (3,220)
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	1,081	1,037
Impairments	1,496	4,146
Accretion on discounted liabilities	18	17
Deferred income taxes	(290)	2
Undistributed equity earnings	(78)	254
Net gain on dispositions	(5)	(87)
Unrealized investment gain	(224)	0
Other	289	52
Working capital adjustments
Accounts and notes receivable	(1,465)	2,684
Inventories	(495)	(1,134)
Prepaid expenses and other current assets	(369)	(40)
Accounts payable	3,723	(2,985)
Taxes and other accruals	313	746
Net Cash Provided by Operating Activities	4,217	1,472
Cash Flows From Investing Activities
Capital expenditures and investments	(1,263)	(2,414)
Return of investments in equity affiliates	236	139
Proceeds from asset dispositions	26	3
Advances/loans—related parties	(310)	(251)
Collection of advances/loans—related parties	1	44
Other	(5)	(87)
Net Cash Used in Investing Activities	(1,315)	(2,566)
Cash Flows From Financing Activities
Issuance of debt	450	3,305
Repayment of debt	(1,485)	(546)
Issuance of common stock	24	6
Repurchase of common stock	0	(443)
Dividends paid on common stock	(1,182)	(1,182)
Distributions to noncontrolling interests	(239)	(201)
Repurchase of noncontrolling interests	(24)	0
Other	(36)	(20)
Net Cash Provided by (Used in) Financing Activities	(2,492)	919
Effect of Exchange Rate Changes on Cash and Cash Equivalents	(27)	23
Net Change in Cash and Cash Equivalents	383	(152)
Cash and cash equivalents at beginning of period	2,514	1,614
Cash and Cash Equivalents at End of Period	$ 2,897	$ 1,462

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Par Value	Capital in Excess of Par	Treasury Stock	Retained Earnings	Accum. Other Comprehensive Loss	Noncontrolling Interests
Beginning balance at Dec. 31, 2019	$ 27,169	$ 6	$ 20,301	$ (16,673)	$ 22,064	$ (788)	$ 2,259
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(3,220)				(3,436)		216
Other comprehensive income (loss)	(184)					(184)
Dividends paid on common stock	(1,182)				(1,182)
Repurchase of common stock	(443)			(443)
Benefit plan activity	54		62		(8)
Transfer of equity interest	305						305
Net distributions to noncontrolling interests	(197)						(197)
Other	3				(2)	5
Ending balance at Sep. 30, 2020	$ 22,305	6	20,363	(17,116)	17,436	(967)	2,583
Beginning balance, common stock issued (in shares) at Dec. 31, 2019	647,416,633
Beginning balance, treasury stock (in shares) at Dec. 31, 2019	206,390,806
Stockholders' Equity, Shares [Roll Forward]
Repurchase of common stock (in shares)	5,381,021
Shares issued - share-based compensation (in shares)	1,155,379
Ending balance, common stock issued (in shares) at Sep. 30, 2020	648,572,012
Ending balance, treasury stock (in shares) at Sep. 30, 2020	211,771,827
Beginning balance at Jun. 30, 2020	$ 23,295	6	20,342	(17,116)	18,631	(1,148)	2,580
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(726)				(799)		73
Other comprehensive income (loss)	181					181
Dividends paid on common stock	(393)				(393)
Benefit plan activity	18		21		(3)
Net distributions to noncontrolling interests	(70)						(70)
Ending balance at Sep. 30, 2020	$ 22,305	6	20,363	(17,116)	17,436	(967)	2,583
Beginning balance, common stock issued (in shares) at Jun. 30, 2020	648,468,487
Beginning balance, treasury stock (in shares) at Jun. 30, 2020	211,771,827
Stockholders' Equity, Shares [Roll Forward]
Repurchase of common stock (in shares)	0
Shares issued - share-based compensation (in shares)	103,525
Ending balance, common stock issued (in shares) at Sep. 30, 2020	648,572,012
Ending balance, treasury stock (in shares) at Sep. 30, 2020	211,771,827
Beginning balance at Dec. 31, 2020	$ 21,523	6	20,383	(17,116)	16,500	(789)	2,539
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	223				44		179
Other comprehensive income (loss)	200					200
Dividends paid on common stock	(1,182)				(1,182)
Benefit plan activity	95		105		(10)
Net distributions to noncontrolling interests	(239)						(239)
Repurchase of noncontrolling interests	(23)				(2)		(21)
Ending balance at Sep. 30, 2021	$ 20,597	6	20,488	(17,116)	15,350	(589)	2,458
Beginning balance, common stock issued (in shares) at Dec. 31, 2020	648,643,223
Beginning balance, treasury stock (in shares) at Dec. 31, 2020	211,771,827
Stockholders' Equity, Shares [Roll Forward]
Repurchase of common stock (in shares)	0
Shares issued - share-based compensation (in shares)	1,228,877
Ending balance, common stock issued (in shares) at Sep. 30, 2021	649,872,100
Ending balance, treasury stock (in shares) at Sep. 30, 2021	211,771,827
Beginning balance at Jun. 30, 2021	$ 20,602	6	20,463	(17,116)	15,345	(549)	2,453
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	488				402		86
Other comprehensive income (loss)	(40)					(40)
Dividends paid on common stock	(394)				(394)
Benefit plan activity	22		25		(3)
Net distributions to noncontrolling interests	(81)						(81)
Ending balance at Sep. 30, 2021	$ 20,597	$ 6	$ 20,488	$ (17,116)	$ 15,350	$ (589)	$ 2,458
Beginning balance, common stock issued (in shares) at Jun. 30, 2021	649,761,235
Beginning balance, treasury stock (in shares) at Jun. 30, 2021	211,771,827
Stockholders' Equity, Shares [Roll Forward]
Repurchase of common stock (in shares)	0
Shares issued - share-based compensation (in shares)	110,865
Ending balance, common stock issued (in shares) at Sep. 30, 2021	649,872,100
Ending balance, treasury stock (in shares) at Sep. 30, 2021	211,771,827

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividends paid per common stock (in usd per share)	$ 0.90	$ 0.90	$ 2.70	$ 2.70

Interim Financial Information

Interim Financial Information	9 Months Ended
	Sep. 30, 2021
Interim Financial Information [Abstract]
Interim Financial Information	Interim Financial InformationThe 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 the consolidated financial position of Phillips 66 and its 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 consolidated financial statements and notes included in our 2020 Annual Report on Form 10-K. The results of operations for the three and nine months ended September 30, 2021, are not necessarily indicative of the results expected for the full year.

Sales and Other Operating Reven

Sales and Other Operating Revenues	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Sales and Other Operating Revenues	Sales and Other Operating Revenues Disaggregated Revenues The following tables present our disaggregated sales and other operating revenues: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Product Line and Services Refined petroleum products $ 24,838 12,573 63,057 37,431 Crude oil resales 3,091 2,198 9,484 6,565 Natural gas liquids (NGL) 2,331 966 6,048 2,645 Services and other * (17) 192 283 1,079 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 Geographic Location** United States $ 24,011 12,125 61,920 36,212 United Kingdom 2,948 1,850 8,070 5,131 Germany 1,194 805 3,049 2,276 Other foreign countries 2,090 1,149 5,833 4,101 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 * Includes derivatives-related activities. See Note 12—Derivatives and Financial Instruments, for additional information. ** Sales and other operating revenues are attributable to countries based on the location of the operations generating the revenues. Contract-Related Assets and Liabilities At September 30, 2021, and December 31, 2020, receivables from contracts with customers were $6,341 million and $3,911 million, respectively. Significant noncustomer balances, such as buy/sell receivables and excise tax receivables, were excluded from these amounts. Our contract-related assets also include payments we make to our marketing customers related to incentive programs. An incentive payment is initially recognized as an asset and subsequently amortized as a reduction to revenue over the contract term, which generally ranges from 5 to 15 years. At September 30, 2021, and December 31, 2020, our asset balances related to such payments were $435 million and $404 million, respectively. Our contract liabilities represent advances from our customers prior to product or service delivery. At September 30, 2021, and December 31, 2020, contract liabilities were immaterial. Remaining Performance Obligations

Credit Losses

Credit Losses	9 Months Ended
	Sep. 30, 2021
Credit Loss [Abstract]
Credit Losses	Credit Losses We are exposed to credit losses primarily through our sales of refined petroleum products, crude oil and NGL. We assess each counterparty’s ability to pay for the products we sell by conducting a credit review. The credit review considers our expected billing exposure and timing for payment and the counterparty’s established credit rating or our assessment of the counterparty’s creditworthiness based on our analysis of their financial statements when a credit rating is not available. We also consider contract terms and conditions, country and political risk, and business strategy in our evaluation. A credit limit is established for each counterparty based on the outcome of this review. We may require collateralized asset support or a prepayment to mitigate credit risk. We monitor our ongoing credit exposure through active review of counterparty balances against contract terms and due dates. Our activities include timely account reconciliations, dispute resolution and payment confirmations. We may employ collection agencies and legal counsel to pursue recovery of defaulted receivables. The negative economic impacts associated with Coronavirus Disease 2019 (COVID-19) have increased the probability that certain of our counterparties may not be able to completely fulfill their obligations in a timely manner. In response, we have enhanced our credit monitoring, sought collateral to support some transactions, and required prepayments from higher-risk counterparties. At September 30, 2021, and December 31, 2020, we reported $8,006 million and $6,522 million of accounts and notes receivable, net of allowances of $36 million and $37 million, respectively. Based on an aging analysis at September 30, 2021, more than 95% of our accounts receivable were outstanding less than 60 days. We are also exposed to credit losses from off-balance sheet exposures, such as guarantees of joint venture debt and standby letters of credit. See Note 10—Guarantees, and Note 11—Contingencies and Commitments, for more information on these off-balance sheet exposures.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of the following: Millions of Dollars September 30 December 31 Crude oil and petroleum products $ 4,015 3,536 Materials and supplies 385 357 $ 4,400 3,893 Inventories valued on the last-in, first-out (LIFO) basis totaled $3,828 million and $3,368 million at September 30, 2021, and December 31, 2020, respectively. The estimated excess of current replacement cost over LIFO cost of inventories amounted to approximately $6.1 billion and $2.7 billion at September 30, 2021, and December 31, 2020, respectively. Certain planned reductions in inventory that are not expected to be replaced by the end of the year cause liquidations of LIFO inventory values. LIFO inventory liquidations decreased our net income by $17 million and $99 million in the three and nine months ended September 30, 2021, respectively. The impact was immaterial for the corresponding periods of 2020.

Investments, Loans and Long-Ter

Investments, Loans and Long-Term Receivables	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Investments, Loans and Long-Term Receivables	Investments, Loans and Long-Term Receivables Equity Investments Dakota Access, LLC (Dakota Access) and Energy Transfer Crude Oil Company, LLC (ETCO) In 2020, the trial court presiding over litigation regarding the Dakota Access Pipeline ordered the U.S. Army Corps of Engineers (USACE) to prepare an Environmental Impact Statement (EIS) relating to an easement under Lake Oahe in North Dakota and later vacated the easement. Although the easement has been vacated, the USACE has indicated that it will not take action to stop pipeline operations while it proceeds with the EIS, which is expected to be completed in the second half of 2022. In May 2021, the court denied a request for an injunction to shut down the pipeline while the EIS is being prepared and in June 2021, dismissed the litigation. It is possible that the litigation could be reopened or new litigation challenging the EIS, once completed, could be filed. In September 2021, Dakota Access filed a writ of certiorari, requesting the U.S. Supreme Court to review the lower court’s judgment that ordered the EIS and vacated the easement. Dakota Access and ETCO have guaranteed repayment of $2.5 billion aggregate principal amount of senior unsecured notes issued by a wholly owned subsidiary of Dakota Access. In addition, Phillips 66 Partners LP (Phillips 66 Partners) and its 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 in certain circumstances relating to the litigation described above. At September 30, 2021, Phillips 66 Partners’ share of the maximum potential equity contributions under the CECU was approximately $631 million. If the pipeline is required to cease operations, and should Dakota Access and ETCO not have sufficient funds to pay ongoing expenses, Phillips 66 Partners also could be required to support its 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. At September 30, 2021, the aggregate book value of Phillips 66 Partners’ investments in Dakota Access and ETCO was $579 million. CF United LLC (CF United) We hold a 50% voting interest and a 48% economic interest in CF United, a retail marketing joint venture with operations primarily on the U.S. West Coast. CF United is considered a variable interest entity (VIE) because our co-venturer has an option to require us to purchase its interest based on a fixed multiple. The put option becomes effective July 1, 2023, and expires on March 31, 2024. The put option is viewed as a variable interest as the purchase price on the exercise date may not represent the then-current fair value of CF United. We have determined that we are not the primary beneficiary because we and our co-venturer jointly direct the activities of CF United that most significantly impact economic performance. At September 30, 2021, our maximum exposure to loss was comprised of our $271 million investment in CF United, and any potential future loss resulting from the put option should the purchase price based on a fixed multiple exceed the then-current fair value of CF United. OnCue Holdings, LLC (OnCue) We hold a 50% interest in OnCue, a joint venture that owns and operates retail convenience stores. We fully guaranteed various debt agreements of OnCue and our co-venturer did not participate in the guarantees. This entity is considered a VIE because our debt guarantees resulted in OnCue not being exposed to all potential losses. We have determined we are not the primary beneficiary because we do not have the power to direct the activities that most significantly impact economic performance. At September 30, 2021, our maximum exposure to loss was $183 million, which represented the book value of our investment in OnCue of $113 million and guaranteed debt obligations of $70 million. Liberty Pipeline LLC (Liberty) In the first quarter of 2021, Phillips 66 Partners’ decision to exit the Liberty Pipeline project resulted in a $198 million before-tax impairment of its investment in Liberty. The impairment is included in the “Impairments” line item on our consolidated statement of operations for the nine months ended September 30, 2021. See Note 7—Impairments, and Note 13—Fair Value Measurements, for additional information regarding the impairment and the techniques used to determine the fair value of Phillips 66 Partners’ investment in Liberty. In April 2021, Phillips 66 Partners transferred its ownership interest in Liberty to its co-venturer for cash and certain pipeline assets with a value that approximated its book value of $46 million at March 31, 2021. Other Investments In September 2021, we acquired 78 million ordinary shares in NOVONIX Limited (NOVONIX), representing a 16% ownership interest, for $150 million. NOVONIX is a Brisbane, Australia-based company listed on the Australian Securities Exchange that develops and supplies materials for lithium-ion batteries. Since we do not have significant influence over the operating and financial policies of NOVONIX and the shares we own have a readily determinable fair value, our investment is recorded at fair value at the end of each reporting period. The fair value of our investment is recorded in the “Investments and long-term receivables” line item on our consolidated balance sheet, and the change in the fair value of our investment, or unrealized gain (loss), is recorded in the “Other income” line item on our consolidated statement of operations. The fair value of our investment in NOVONIX was $374 million at September 30, 2021, and the unrealized investment gain was $224 million for the three and nine months ended September 30, 2021. See Note 13—Fair Value Measurements, for additional information regarding the recurring fair value measurement of our investment in NOVONIX. Related Party Loans We and our co-venturer provided member loans to WRB Refining LP (WRB). At September 30, 2021, our 50% share of the outstanding member loan balance, including accrued interest, was $593 million.

Properties, Plants and Equipmen

Properties, Plants and Equipment	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Properties, Plants and Equipment	Properties, Plants and Equipment Our gross investment in properties, plants and equipment (PP&E) and the associated accumulated depreciation and amortization (Accum. D&A) balances were as follows: Millions of Dollars September 30, 2021 December 31, 2020 Gross Accum. Net Gross Accum. Net Midstream $ 12,435 2,975 9,460 12,313 2,815 9,498 Chemicals — — — — — — Refining 25,378 14,033 11,345 24,647 12,019 12,628 Marketing and Specialties 1,802 1,028 774 1,815 1,007 808 Corporate and Other 1,524 726 798 1,448 666 782 $ 41,139 18,762 22,377 40,223 16,507 23,716

Impairments

Impairments	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Impairments	Impairments Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Midstream $ 10 204 208 1,365 Refining 1,288 911 1,288 2,756 Corporate and Other — 25 — 25 Total impairments $ 1,298 1,140 1,496 4,146 Equity Investments Liberty In the first quarter of 2021, Phillips 66 Partners decided to exit the Liberty Pipeline project, which had previously been deferred due to the challenging business environment caused by the COVID-19 pandemic. As a result, Phillips 66 Partners recorded a $198 million before-tax impairment to reduce the book value of its investment in Liberty at March 31, 2021, to estimated fair value. Red Oak Pipeline LLC (Red Oak) In the third quarter of 2020, the Red Oak Pipeline project was canceled. As a result, we recorded an $84 million before-tax impairment to reduce the carrying value of our investment to our share of the estimated salvage value of the joint venture’s assets at September 30, 2020. DCP Midstream, LLC (DCP Midstream) In the first quarter of 2020, the market value of DCP Partners, LP (DCP Partners) common units declined by approximately 85%. As a result, at March 31, 2020, the fair value of our investment in DCP Midstream was significantly lower than its book value. We concluded this difference was not temporary primarily due to its magnitude, and we recorded a $1,161 million before-tax impairment of our investment in the first quarter of 2020. PP&E and Intangible Assets Alliance Refinery In the third quarter of 2021, we identified impairment indicators related to our Alliance Refinery as a result of damages sustained from Hurricane Ida and our reassessment of the role this refinery will play in our refining portfolio. Accordingly, we assessed the refinery asset group for impairment by performing an analysis that considered several usage scenarios, including selling or converting the asset group to an alternative use. Based on our analysis, we concluded that the carrying value of the asset group was not recoverable. As a result, we recorded a $1,298 million before-tax impairment to reduce the carrying value of net PP&E in this asset group to its fair value of approximately $200 million. $1,288 million of the impairment charge was recorded in our Refining segment and $10 million was recorded in our Midstream segment. San Francisco Refinery In the third quarter of 2020, we announced a plan to reconfigure our San Francisco Refinery to produce renewable fuels at the Rodeo refining facility in Rodeo, California. We assessed the San Francisco Refinery asset group for impairment and concluded that the carrying value of the asset group was not recoverable. As a result, we recorded a $1,030 million before-tax impairment to reduce the carrying value of the net PP&E and intangible assets in this asset group to its fair value of $940 million. The impairment resulted in a reduction of net PP&E totaling $1,009 million and intangible assets of $21 million. This impairment was primarily related to our Refining segment, with the exception of $120 million that was related to PP&E in our Midstream segment. Goodwill Our stock price declined significantly in the first quarter of 2020, mainly due to the disruption in global commodity and equity markets related to the COVID-19 pandemic. We assessed our goodwill for impairment due to the decline in our market capitalization and concluded that the carrying value of our Refining reporting unit at March 31, 2020, was greater than its fair value by an amount in excess of its goodwill balance. Accordingly, we recorded a before-tax goodwill impairment charge of $1,845 million in our Refining segment during the first quarter of 2020. These impairment charges are included within the “Impairments” line item on our consolidated statement of operations. See Note 13—Fair Value Measurements, for additional information on the determination of fair value used to record these impairments. Outlook The COVID-19 pandemic continues to disrupt economic activities globally. Reduced demand for refined petroleum products resulted in low refining margins and decreased volumes through refineries and logistics infrastructure in 2020. Global refined product demand has been steadily recovering through 2021 due to the easing of pandemic restrictions and the administration of COVID-19 vaccines. Consequently, refining margins have improved, as has volume throughput. The depth and duration of the economic consequences of the COVID-19 pandemic remain uncertain and we continue to monitor our asset and investment portfolio. The consequences of the sustained disruption of economic activities by the pandemic may include additional asset impairments and portfolio rationalization in the future.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share The numerator of basic earnings (loss) per share (EPS) is net income (loss) attributable to Phillips 66, adjusted for noncancelable dividends paid on unvested share-based employee awards during the vesting period (participating securities) and the premium paid for the repurchase of noncontrolling interests. The denominator of basic EPS is the sum of the daily weighted-average number of common shares outstanding during the periods presented and fully vested stock and unit awards that have not yet been issued as common stock. The numerator of diluted EPS is also based on net income (loss) attributable to Phillips 66, which is reduced by dividend equivalents paid on participating securities for which the dividends are more dilutive than the participation of the awards in the earnings (loss) of the periods presented, and the premium paid for the repurchase of noncontrolling interests. To the extent unvested stock, unit or option awards and vested unexercised stock options are dilutive, they are included with the weighted-average common shares outstanding in the denominator. Treasury stock is excluded from the denominator in both basic and diluted EPS. Three Months Ended Nine Months Ended 2021 2020 2021 2020 Basic Diluted Basic Diluted Basic Diluted Basic Diluted Amounts Attributed to Phillips 66 Common Stockholders (millions) : Net income (loss) attributable to Phillips 66 $ 402 402 (799) (799) 44 44 (3,436) (3,436) Income allocated to participating securities (2) (2) (2) (2) (7) (7) (6) (6) Premium paid for the repurchase of noncontrolling interests — — — — (2) (2) — — Net income (loss) available to common stockholders $ 400 400 (801) (801) 35 35 (3,442) (3,442) Weighted-average common shares outstanding (thousands) : 438,067 440,193 436,783 438,916 437,783 439,880 437,492 439,670 Effect of share-based compensation 2,126 175 2,133 — 2,097 379 2,178 — Weighted-average common shares outstanding—EPS 440,193 440,368 438,916 438,916 439,880 440,259 439,670 439,670 Earnings (Loss) Per Share of Common Stock (dollars) $ 0.91 0.91 (1.82) (1.82) 0.08 0.08 (7.83) (7.83)

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt 2021 Activities Debt Issuances and Repayments In September 2021, Phillips 66 repaid the $500 million of outstanding borrowings under the delayed draw term loan facility due November 2023 described below under “Term Loan Facility.” In April 2021, Phillips 66 Partners entered into a $450 million term loan agreement and borrowed the full amount. The term loan agreement has a maturity date of April 5, 2022, and the outstanding borrowings can be repaid at any time and from time to time, in whole or in part, without premium or penalty. Borrowings bear interest at a floating rate based on either a Eurodollar rate or a reference rate, plus a margin of 0.875%. Proceeds were primarily used to repay amounts borrowed under Phillips 66 Partners’ $750 million revolving credit facility. In April 2021, Phillips 66 Partners repaid $50 million of its tax-exempt bonds upon maturity. In February 2021, Phillips 66 repaid $500 million outstanding principal balance of its floating-rate senior notes upon maturity. At September 30, 2021, no borrowings were outstanding and $1 million in letters of credit had been drawn under Phillips 66 Partners’ $750 million revolving credit facility, compared with outstanding borrowings of $415 million and $1 million in letters of credit drawn under the facility at December 31, 2020. Debt Classification At September 30, 2021, $1 billion of Phillips 66’s debt due within a year was classified as long-term debt based on its intent and ability to refinance the obligation with long-term debt. 2020 Activities Senior Unsecured Notes On June 10, 2020, Phillips 66 closed its public offering of $1 billion aggregate principal amount of senior unsecured notes consisting of: • $150 million aggregate principal amount of 3.850% Senior Notes due 2025. • $850 million aggregate principal amount of 2.150% Senior Notes due 2030. On April 9, 2020, Phillips 66 closed its public offering of $1 billion aggregate principal amount of senior unsecured notes consisting of: • $500 million aggregate principal amount of 3.700% Senior Notes due 2023. • $500 million aggregate principal amount of 3.850% Senior Notes due 2025. Interest on the Senior Notes due 2023 is payable semiannually on April 6 and October 6 of each year, commencing on October 6, 2020. The Senior Notes due 2025 issued on June 10, 2020, constitute a further issuance of the Senior Notes due 2025 originally issued on April 9, 2020. The $650 million in aggregate principal amount of Senior Notes due 2025 is treated as a single class of debt securities. Interest on the Senior Notes due 2025 is payable semiannually on April 9 and October 9 of each year, commencing on October 9, 2020. Interest on the Senior Notes due 2030 is payable semiannually on June 15 and December 15 of each year, commencing on December 15, 2020. Proceeds received from the public offerings of senior unsecured notes on June 10, 2020, and April 9, 2020, were $1,008 million exclusive of accrued interest received, and $993 million, respectively, net of underwriters’ discounts or premiums and commissions, as well as debt issuance costs. These proceeds were used for general corporate purposes. Term Loan Facility On March 19, 2020, Phillips 66 entered into a $1 billion 364-day delayed draw term loan agreement (the Facility) and borrowed $1 billion under the Facility shortly thereafter. On April 6, 2020, Phillips 66 increased the size of the Facility to $2 billion, and in June 2020, the Facility was amended to extend the commitment period to September 19, 2020. We did not draw additional amounts under the Facility before the end of the commitment period or further extend the commitment period. In November 2020, we repaid $500 million of borrowings outstanding under the Facility, and the Facility was amended to extend the maturity date of the remaining $500 million outstanding borrowings from March 18, 2021, to November 20, 2023. Borrowings under the Facility bear interest at a floating rate based on either a Eurodollar rate or a reference rate, plus a margin determined by the credit rating of Phillips 66’s senior unsecured long-term debt. Phillips 66 used the proceeds for general corporate purposes. Other Debt Repayments In April 2020, Phillips 66 repaid $300 million outstanding principal balance of its floating-rate notes due April 2020 and the $200 million outstanding principal balance of its term loan facility due April 2020. Also in April 2020, Phillips 66 Partners repaid $25 million of its tax-exempt bonds upon maturity.

Guarantees

Guarantees	9 Months Ended
	Sep. 30, 2021
Guarantees [Abstract]
Guarantees	Guarantees At September 30, 2021, we were liable for certain contingent obligations under various contractual arrangements as described below. We recognize a liability for the fair value of our obligation as a guarantor for newly issued or modified guarantees. Unless the carrying amount of the liability is noted below, we have not recognized a liability either because the guarantees were issued prior to December 31, 2002, or because the fair value of the obligation is immaterial. In addition, unless otherwise stated, we are not currently performing with any significance under the guarantees and expect future performance to be either immaterial or have only a remote chance of occurrence. Lease Residual Value Guarantees Under the operating lease agreement for our headquarters facility in Houston, Texas, we have the option, at the end of the lease term in September 2025, to request to renew the lease, purchase the facility or assist the lessor in marketing it for resale. We have a residual value guarantee associated with the operating lease agreement with a maximum potential future exposure of $514 million at September 30, 2021. We also have residual value guarantees associated with railcar and airplane leases with maximum potential future exposures totaling $209 million. These leases have remaining terms of up to ten years. Guarantees of Joint Venture Obligations In March 2019, Phillips 66 Partners and its co-venturers in Dakota Access provided a CECU in conjunction with a senior unsecured notes offering. See Note 5—Investments, Loans and Long-Term Receivables, for additional information on Dakota Access and the CECU. At September 30, 2021, we also had other guarantees outstanding primarily for our portion of certain joint venture debt, which have remaining terms of up to four years. The maximum potential future exposures under these guarantees were approximately $122 million. Payment would be required if a joint venture defaults on its obligations. Indemnifications Over the years, we have entered into various agreements to sell ownership interests in certain corporations, joint ventures and assets that gave rise to indemnification. Agreements associated with these sales include indemnifications for taxes, litigation, environmental liabilities, permits and licenses, employee claims, and real estate tenant defaults. The provisions of these indemnifications vary greatly. The majority of these indemnifications are related to environmental issues, which generally have indefinite terms and potentially unlimited exposure. At September 30, 2021, and December 31, 2020, the carrying amount of recorded indemnifications was $146 million and $145 million, respectively. We amortize the indemnification liability over the relevant time period, if one exists, based on the facts and circumstances surrounding each type of indemnity. In cases where the indemnification term is indefinite, we will reverse the liability when we have information to support the reversal. Although it is reasonably possible future payments may exceed amounts recorded, due to the nature of the indemnifications, it is not possible to make a reasonable estimate of the maximum potential amount of future payments. At September 30, 2021, and December 31, 2020, environmental accruals for known contamination of $108 million and $104 million, respectively, were included in the carrying amount of the recorded indemnifications noted above. These environmental accruals were primarily included in the “Asset retirement obligations and accrued environmental costs” line item on our consolidated balance sheet. For additional information about environmental liabilities, see Note 11—Contingencies and Commitments. Indemnification and Release Agreement In 2012, in connection with our separation from ConocoPhillips, we entered into an Indemnification and Release Agreement. This agreement governs the treatment between ConocoPhillips and us of matters relating to indemnification, insurance, litigation responsibility and management, and litigation document sharing and cooperation arising in connection with the separation. Generally, the agreement provides for cross indemnities principally designed to place financial responsibility for the obligations and liabilities of our business with us and financial responsibility for the obligations and liabilities of ConocoPhillips’ business with ConocoPhillips. The agreement also establishes procedures for handling claims subject to indemnification and related matters.

Contingencies and Commitments

Contingencies and Commitments	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Commitments	Contingencies and Commitments A number of lawsuits involving a variety of claims that arose in the ordinary course of business have been filed against us or are subject to indemnifications provided by 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 active and inactive sites. We regularly assess the need for financial 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 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 international, federal, state and local environmental laws and regulations. When we prepare our consolidated financial statements, we record accruals for environmental liabilities based on management’s best estimates, using information available at the time. We measure estimates and base contingent liabilities on currently available facts, existing technology and presently enacted laws and regulations, taking into account stakeholder and business considerations. When measuring contingent environmental liabilities, we also consider our prior experience in remediation of contaminated sites, other companies’ cleanup experience, and data released by the EPA 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. Although liability for environmental remediation costs is generally joint and several for federal sites and frequently so for state sites, we are usually only one of many companies alleged to have liability at a particular site. Due to such joint and several liabilities, we could be responsible for all cleanup costs related to any site at which we have been designated as a potentially responsible party. We have been successful to date in sharing cleanup costs with other financially sound companies. Many of the sites for which we are potentially responsible are still under investigation by the EPA or the state agencies concerned. Prior to actual cleanup, those potentially responsible normally assess the site conditions, apportion responsibility and determine the appropriate remediation. In some instances, we may have no liability or may attain a settlement of liability. Where it appears that other potentially responsible parties may be financially unable to bear their proportional share, we consider this inability in estimating our potential liability, and we adjust our accruals accordingly. As a result of various acquisitions in the past, we assumed certain environmental obligations. Some of these environmental obligations are mitigated by indemnifications made by others for our benefit, although some of the indemnifications are subject to dollar and time limits. We are currently participating in environmental assessments and cleanups at numerous federal Superfund and comparable state sites. After an assessment of environmental exposures for cleanup and other costs, we make accruals on an undiscounted basis (except those pertaining to sites acquired in a business combination, which we record on a discounted basis) for planned investigation and remediation activities for sites where it is probable future costs will be incurred and these costs can be reasonably estimated. At September 30, 2021, our total environmental accruals were $453 million, compared with $427 million at December 31, 2020. We expect to incur a substantial amount of these expenditures within the next 30 years. We have not reduced these accruals for possible insurance recoveries. In the future, we may be involved in additional environmental assessments, cleanups and proceedings. Legal Proceedings Our 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. Our process facilitates the early evaluation and quantification of potential exposures in individual cases and enables the 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, our legal organization regularly assesses the adequacy of current accruals and determines if adjustment of existing accruals, or establishment of new accruals, is required. Other Contingencies We have contingent liabilities resulting from throughput agreements with pipeline and processing companies not associated with financing arrangements. Under these agreements, we may be required to provide any such company with additional funds through advances and penalties for fees related to throughput capacity not utilized. At September 30, 2021, we had performance obligations secured by letters of credit and bank guarantees of $740 million related to various purchase and other commitments incident to the ordinary conduct of business.

Derivatives and Financial Instr

Derivatives and Financial Instruments	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Financial Instruments	Derivatives and Financial Instruments Derivative Instruments We use financial and commodity-based derivative contracts to manage exposures to fluctuations in commodity prices, interest rates and foreign currency exchange rates, or to capture market opportunities. Because we do not apply hedge accounting for commodity derivative contracts, all realized and unrealized gains and losses from commodity derivative contracts are recognized in our consolidated statement of operations. Gains and losses from derivative contracts held for trading not directly related to our physical business are reported net in the “Other income” line item on our consolidated statement of operations. Cash flows from all our derivative activity for the periods presented appear in the operating section on our consolidated statement of cash flows. Purchase and sales contracts with firm minimum notional volumes for commodities that are readily convertible to cash are recorded on our consolidated balance sheet as derivatives unless the contracts are eligible for, and we elect, the normal purchases and normal sales exception, whereby the contracts are recorded on an accrual basis. We generally apply the normal purchases and normal sales exception to eligible crude oil, refined petroleum product, NGL, natural gas, renewable feedstock, and power commodity contracts to purchase or sell quantities we expect to use or sell in the normal course of business. All other derivative instruments are recorded at fair value on our consolidated balance sheet. For further information on the fair value of derivatives, see Note 13—Fair Value Measurements. Commodity Derivative Contracts —We sell into or receive supply from the worldwide crude oil, refined petroleum product, NGL, natural gas, renewable feedstock, and electric power markets, exposing our revenues, purchases, cost of operating activities and cash flows to fluctuations in the prices for these commodities. Generally, our policy is to remain exposed to the market prices of commodities; however, we use futures, forwards, swaps and options in various markets to balance physical systems, meet customer needs, manage price exposures on specific transactions, and do a limited amount of trading not directly related to our physical business, all of which may reduce our exposure to fluctuations in market prices. We also use the market knowledge gained from these activities to capture market opportunities such as moving physical commodities to more profitable locations, storing commodities to capture seasonal or time premiums, and blending commodities to capture quality upgrades. The following table indicates the consolidated balance sheet line items that include the fair values of commodity derivative assets and liabilities. The balances in the following table are presented on a gross basis, before the effects of counterparty and collateral netting. However, we have elected to present our commodity derivative assets and liabilities with the same counterparty on a net basis on our consolidated balance sheet when the legal right of offset exists. Millions of Dollars September 30, 2021 December 31, 2020 Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Assets Liabilities Assets Liabilities Assets Prepaid expenses and other current assets $ 38 (2) (4) 32 13 — — 13 Other assets 15 (5) — 10 5 (4) — 1 Liabilities Other accruals 1,990 (2,194) 145 (59) 665 (721) 46 (10) Other liabilities and deferred credits 4 (6) — (2) — — — — Total $ 2,047 (2,207) 141 (19) 683 (725) 46 4 At September 30, 2021, and December 31, 2020, there was no material cash collateral received or paid that was not offset on our consolidated balance sheet. The realized and unrealized gains (losses) incurred from commodity derivatives, and the line items where they appear on our consolidated statement of operations, were: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Sales and other operating revenues $ (214) 20 (530) 519 Other income 11 — 30 9 Purchased crude oil and products 66 (16) (282) 301 Net gain (loss) from commodity derivative activity $ (137) 4 (782) 829 The following table summarizes our material net exposures resulting from outstanding commodity derivative contracts. These financial and physical derivative contracts are primarily used to manage price exposure on our underlying operations. The underlying exposures may be from nonderivative positions such as inventory volumes. Financial derivative contracts may also offset physical derivative contracts, such as forward purchase and sales contracts. The percentage of our derivative contract volumes expiring within the next 12 months was more than 95% at September 30, 2021, and December 31, 2020. Open Position September 30 December 31 Commodity Crude oil, refined petroleum products, NGL and renewable feedstocks (millions of barrels) (32) (13) Interest Rate Derivative Contracts —In 2016, we entered into interest rate swaps to hedge the variability of lease payments on our headquarters facility. These monthly lease payments vary based on monthly changes in the one-month London Interbank Offered Rate (LIBOR) and changes, if any, in our credit rating. The pay-fixed, receive-floating interest rate swaps have an aggregate notional value of $650 million and ended in April 2021. These swaps were designated as cash flow hedges. We reported the mark-to-market gains or losses on our interest rate swaps designated as highly effective cash flow hedges as a component of other comprehensive income (loss), and reclassified such gains and losses into earnings (loss) in the same period during which the hedged transaction affected earnings (loss). Net realized gains and losses from settlements of the swaps were immaterial for the three and nine months ended September 30, 2021 and 2020. Credit Risk from Derivative Instruments The credit risk from our derivative contracts, such as forwards and swaps, derives from the counterparty to the transaction. Individual counterparty exposure is managed within predetermined credit limits and includes the use of cash-call margins when appropriate, thereby reducing the risk of significant nonperformance. We also use futures, swaps and option contracts that have a negligible credit risk because these trades are cleared with an exchange clearinghouse and subject to mandatory margin requirements, typically on a daily basis, until settled. Certain of our derivative instruments contain provisions that require us to post collateral if the derivative exposure exceeds a threshold amount. We have contracts with fixed threshold amounts and other contracts with variable threshold amounts that are contingent on our credit rating. The variable threshold amounts typically decline for lower credit ratings, while both the variable and fixed threshold amounts typically revert to zero if our credit ratings fall below investment grade. Cash is the primary collateral in all contracts; however, many contracts also permit us to post letters of credit as collateral. The aggregate fair values of all derivative instruments with such credit-risk-related contingent features that were in a liability position were immaterial at September 30, 2021, and December 31, 2020.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Recurring Fair Value Measurements We carry certain assets and liabilities at fair value, which we measure at the reporting date using the price that would be received to sell an asset or paid to transfer a liability (i.e., an exit price), and disclose the quality of these fair values based on the valuation inputs used in these measurements under the following hierarchy: • Level 1: Fair value measured with unadjusted quoted prices from an active market for identical assets or liabilities. • Level 2: Fair value measured either with: (1) adjusted quoted prices from an active market for similar assets or liabilities; or (2) other valuation inputs that are directly or indirectly observable. • Level 3: Fair value measured with unobservable inputs that are significant to the measurement. We classify the fair value of an asset or liability based on the significance of its observable or unobservable inputs to the measurement. However, the fair value of an asset or liability initially reported as Level 3 will be subsequently reported as Level 2 if the unobservable inputs become inconsequential to its measurement or corroborating market data becomes available. Conversely, an asset or liability initially reported as Level 2 will be subsequently reported as Level 3 if corroborating market data becomes unavailable. We used the following methods and assumptions to estimate the fair value of financial instruments: • Cash and cash equivalents —The carrying amount reported on our consolidated balance sheet approximates fair value. • Accounts and notes receivable —The carrying amount reported on our consolidated balance sheet approximates fair value. • Derivative instruments —We fair value our exchange-traded contracts based on quoted market prices obtained from the New York Mercantile Exchange, the Intercontinental Exchange or other exchanges, and classify them as Level 1 in the fair value hierarchy. When exchange-cleared contracts lack sufficient liquidity, or are valued using either adjusted exchange-provided prices or nonexchange quotes, we classify those contracts as Level 2. Physical commodity forward purchase and sales contracts and over-the-counter (OTC) financial swaps are generally valued using forward quotes provided by brokers and price index developers, such as Platts and Oil Price Information Service. We corroborate these quotes with market data and classify the resulting fair values as Level 2. When forward market prices are not available, we estimate fair value using the forward price of a similar commodity, adjusted for the difference in quality or location. In certain less liquid markets or for longer-term contracts, forward prices are not as readily available. In these circumstances, physical commodity purchase and sales contracts and OTC swaps are valued using internally developed methodologies that consider historical relationships among various commodities that result in management’s best estimate of fair value. We classify these contracts as Level 3. Physical and OTC commodity options are valued using industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and contractual prices for the underlying instruments, as well as other relevant economic measures. The degree to which these inputs are observable in the forward markets determines whether the options are classified as Level 2 or 3. We use a midmarket pricing convention (the midpoint between bid and ask prices). When appropriate, valuations are adjusted to reflect credit considerations, generally based on available market evidence. We determine the fair value of our interest rate swaps based on observable market valuations for interest rate swaps that have notional amounts, terms and pay and reset frequencies similar to ours. • Rabbi trust assets —These deferred compensation investments are measured at fair value using unadjusted quoted prices available from national securities exchanges and are therefore categorized as Level 1 in the fair value hierarchy. • Investment in NOVONIX —Our investment in NOVONIX is measured at fair value using unadjusted quoted prices available from Australian Securities Exchange and is therefore categorized as Level 1 in the fair value hierarchy. • Debt —The carrying amount of our floating-rate debt approximates fair value. The fair value of our fixed-rate debt is estimated based on observable market prices. The following tables display the fair value hierarchy for our financial assets and liabilities either accounted for or disclosed at fair value on a recurring basis. These values are determined by treating each contract as the fundamental unit of account; therefore, derivative assets and liabilities with the same counterparty are shown on a gross basis in the hierarchy sections of these tables, before the effects of counterparty and collateral netting. The following tables also reflect the effect of netting derivative assets and liabilities with the same counterparty for which we have the legal right of offset and collateral netting. The carrying values and fair values by hierarchy of our financial assets and liabilities, either carried or disclosed at fair value, including any effects of counterparty and collateral netting, were: Millions of Dollars September 30, 2021 Fair Value Hierarchy Total Fair Value of Gross Assets & Liabilities Effect of Counterparty Netting Effect of Collateral Netting Difference in Carrying Value and Fair Value Net Carrying Value Presented on the Balance Sheet Level 1 Level 2 Level 3 Commodity Derivative Assets Exchange-cleared instruments $ 1,093 923 — 2,016 (2,001) (4) — 11 Physical forward contracts — 31 — 31 — — — 31 Rabbi trust assets 152 — — 152 N/A N/A — 152 Investment in NOVONIX 374 — — 374 N/A N/A — 374 $ 1,619 954 — 2,573 (2,001) (4) — 568 Commodity Derivative Liabilities Exchange-cleared instruments $ 1,227 919 — 2,146 (2,001) (145) — — Physical forward contracts — 61 — 61 — — — 61 Floating-rate debt — 925 — 925 N/A N/A — 925 Fixed-rate debt, excluding finance leases — 15,416 — 15,416 N/A N/A (1,736) 13,680 $ 1,227 17,321 — 18,548 (2,001) (145) (1,736) 14,666 Millions of Dollars December 31, 2020 Fair Value Hierarchy Total Fair Value of Gross Assets & Liabilities Effect of Counterparty Netting Effect of Collateral Netting Difference in Carrying Value and Fair Value Net Carrying Value Presented on the Balance Sheet Level 1 Level 2 Level 3 Commodity Derivative Assets Exchange-cleared instruments $ 314 356 — 670 (669) — — 1 Physical forward contracts — 13 — 13 — — — 13 Rabbi trust assets 143 — — 143 N/A N/A — 143 $ 457 369 — 826 (669) — — 157 Commodity Derivative Liabilities Exchange-cleared instruments $ 351 364 — 715 (669) (46) — — Physical forward contracts — 10 — 10 — — — 10 Interest-rate derivatives — 3 — 3 — — — 3 Floating-rate debt — 1,940 — 1,940 N/A N/A — 1,940 Fixed-rate debt, excluding finance leases — 15,597 — 15,597 N/A N/A (1,927) 13,670 $ 351 17,914 — 18,265 (669) (46) (1,927) 15,623 The rabbi trust assets and investment in NOVONIX are recorded in the “Investments and long-term receivables” line item, and floating-rate and fixed-rate debt are recorded in the “Short-term debt” and “Long-term debt” line items on our consolidated balance sheet. See Note 12—Derivatives and Financial Instruments, for information regarding where the assets and liabilities related to our commodity derivatives are recorded on our consolidated balance sheet. Nonrecurring Fair Value Measurements Equity Investments In the first quarter of 2021, Phillips 66 Partners wrote down the book value of its investment in Liberty to estimated fair value using a Level 3 nonrecurring fair value measurement. This nonrecurring measurement was based on the estimated fair value of Phillip 66 Partners’ share of the joint venture’s pipeline assets and net working capital. See Note 5—Investments, Loans and Long-Term Receivables, for more information regarding Phillips 66 Partners’ transfer of its ownership in Liberty to its co-venturer in April 2021. In the first quarter of 2020, the nonrecurring fair value measurement used to record an impairment of our DCP Midstream investment was the fair value of our share of DCP Midstream’s limited partner interest in DCP Partners, which was estimated based on average market prices of DCP Partners common units for a multi-day trading period encompassing March 31, 2020. This valuation resulted in a Level 2 nonrecurring fair value measurement. PP&E and Intangible Assets In the third quarter of 2021, we remeasured the carrying value of the net PP&E of our Alliance Refinery asset group to fair value. The fair value of PP&E was determined using a combination of the income, cost and sales comparison approaches. The income approach used a discounted cash flow model that requires various observable and non-observable inputs, such as commodity prices, margins, operating rates, sales volumes, operating expenses, capital expenditures, terminal-year values and a risk-adjusted discount rate. The cost approach used assumptions for the current replacement costs of similar plant and equipment assets adjusted for estimated physical deterioration, functional obsolescence and economic obsolescence. The sales comparison approach used the value of similar properties recently sold or currently offered for sale. This valuation resulted in a Level 3 nonrecurring fair value measurement. In the third quarter of 2020, we remeasured the carrying value of the net PP&E and intangible assets of our San Francisco Refinery asset group to fair value. The estimated fair value of the plants, equipment and intangible assets was determined using a replacement cost approach adjusted, as applicable, for physical deterioration, functional obsolescence and economic obsolescence. The estimated fair value of the properties was determined using a sales comparison approach. This valuation resulted in a Level 3 nonrecurring fair value measurement. Goodwill The carrying value of the Refining reporting unit’s goodwill was remeasured to fair value on a nonrecurring basis in the first quarter of 2020. The fair value of the Refining reporting unit was calculated by weighting the results from the income approach and the market approach. The income approach used a discounted cash flow model that included various observable and nonobservable inputs, such as prices, volumes, expenses, capital expenditures, discount rates and projected long-term growth rates and terminal values. The market approach used peer company enterprise values relative to current and future net income (loss) before net interest expense, income taxes, depreciation and amortization (EBITDA) projections to arrive at an average multiple. This multiple was applied to the reporting unit’s current and projected EBITDA, with consideration for an estimated market participant acquisition premium. The resulting Level 3 fair value estimate was less than the Refining reporting unit’s carrying value by an amount that exceeded the existing goodwill balance of the reporting unit. As a result, the Refining reporting unit’s goodwill was impaired to zero. As part of our impairment analysis, the fair value of all reporting units was reconciled to the company’s market capitalization. See Note 7—Impairments, for additional information on the above impairments.

Pension and Postretirement Plan

Pension and Postretirement Plans	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Pension and Postretirement Plans	Pension and Postretirement Plans The components of net periodic benefit cost for the three and nine months ended September 30, 2021 and 2020, were as follows: Millions of Dollars Pension Benefits Other Benefits 2021 2020 2021 2020 U.S. Int’l. U.S. Int’l. Components of Net Periodic Benefit Cost Three Months Ended September 30 Service cost $ 37 9 35 7 1 1 Interest cost 20 5 21 5 2 2 Expected return on plan assets (39) (15) (38) (12) — — Amortization of prior service credit — — — — (1) (1) Recognized net actuarial loss 8 7 21 4 — — Settlements 18 — 17 — — — Net periodic benefit cost* $ 44 6 56 4 2 2 Nine Months Ended September 30 Service cost $ 111 26 102 21 4 4 Interest cost 60 14 70 16 4 5 Expected return on plan assets (121) (44) (121) (37) — — Amortization of prior service credit — — — — (2) (2) Recognized net actuarial loss (gain) 37 19 50 12 (1) — Settlements 47 — 56 — — — Net periodic benefit cost* $ 134 15 157 12 5 7 * Included in the “Operating expenses” and “Selling, general and administrative expenses” line items on our consolidated statement of operations. During the nine months ended September 30, 2021, we contributed $37 million to our U.S. pension and other postretirement benefit plans and $20 million to our international pension plans. We currently expect to make additional contributions of approximately $16 million to our U.S. pension and other postretirement benefit plans and $8 million to our international pension plans during the remainder of 2021.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Changes in the balances of each component of accumulated other comprehensive loss were as follows: Millions of Dollars Defined Benefit Plans Foreign Currency Translation Hedging Accumulated Other Comprehensive Loss December 31, 2020 $ (809) 25 (5) (789) Other comprehensive income (loss) before reclassifications 184 (68) 1 117 Amounts reclassified from accumulated other comprehensive loss Defined benefit plans* Amortization of net actuarial loss, prior service credit and settlements 82 — — 82 Foreign currency translation — — — — Hedging — — 1 1 Net current period other comprehensive income (loss) 266 (68) 2 200 September 30, 2021 $ (543) (43) (3) (589) December 31, 2019 $ (656) (131) (1) (788) Other comprehensive loss before reclassifications (221) (44) (8) (273) Amounts reclassified from accumulated other comprehensive loss Defined benefit plans* Amortization of net actuarial loss, prior service credit and settlements 86 — — 86 Foreign currency translation — — — — Hedging — — 3 3 Net current period other comprehensive loss (135) (44) (5) (184) Other — 5 — 5 September 30, 2020 $ (791) (170) (6) (967) * Included in the computation of net periodic benefit cost. See Note 14—Pension and Postretirement Plans, for additional information.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Significant transactions with related parties were: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Operating revenues and other income (a) $ 1,005 450 2,734 1,337 Purchases (b) 3,980 1,612 9,789 4,868 Operating expenses and selling, general and administrative expenses (c) 80 65 215 171 (a) We sold NGL, other petrochemical feedstocks and solvents to Chevron Phillips Chemical Company LLC (CPChem), NGL and certain feedstocks to DCP Midstream, gas oil and hydrogen feedstocks to Excel Paralubes (Excel), and refined petroleum products to several of our equity affiliates in the Marketing and Specialties segment, including OnCue and CF United. We also sold certain feedstocks and intermediate products to WRB and acted as an agent for WRB in supplying crude oil and other feedstocks for a fee. In addition, we charged several of our equity affiliates, including CPChem, for the use of common facilities, such as steam generators, waste and water treaters and warehouse facilities. (b) We purchased crude oil, refined petroleum products, NGL and solvents from WRB. We also purchased natural gas and NGL from DCP Midstream and CPChem, as well as other feedstocks from various equity affiliates, for use in our refinery and fractionation processes. In addition, we purchased base oils and fuel products from Excel for use in our specialty and refining businesses. We paid NGL fractionation fees to CPChem. We also paid fees to various pipeline equity affiliates for transporting crude oil, refined petroleum products and NGL. (c) We paid consignment fees to CF United, and utility and processing fees to various equity affiliates.

Segment Disclosures and Related

Segment Disclosures and Related Information	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Segment Disclosures and Related Information	Segment Disclosures and Related Information Our operating segments are: 1) Midstream— Provides crude oil and refined petroleum product transportation, terminaling and processing services, as well as natural gas and NGL transportation, storage, fractionation, processing, and marketing services, mainly in the United States. The Midstream segment includes our master limited partnership (MLP), Phillips 66 Partners, our 50% equity investment in DCP Midstream, and our investment in NOVONIX. 2) Chemicals— Consists of our 50% equity investment in CPChem, which manufactures and markets petrochemicals and plastics on a worldwide basis. 3) Refining— Refines crude oil and other feedstocks into petroleum products, such as gasoline, distillates and aviation fuels, at 13 refineries in the United States and Europe. 4) Marketing and Specialties— Purchases for resale and markets refined petroleum products, mainly in the United States and Europe. In addition, this segment includes the manufacturing and marketing of specialty products. Corporate and Other includes general corporate overhead, interest expense, our investment in new technologies, and various other corporate activities. Corporate assets include all cash, cash equivalents and income tax-related assets. Intersegment sales are at prices that we believe approximate market. Analysis of Results by Operating Segment Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Sales and Other Operating Revenues * Midstream Total sales $ 3,067 1,458 8,049 4,096 Intersegment eliminations (802) (446) (2,138) (1,323) Total Midstream 2,265 1,012 5,911 2,773 Chemicals 1 1 3 3 Refining Total sales 20,206 10,434 53,939 31,567 Intersegment eliminations (12,853) (6,286) (32,826) (18,356) Total Refining 7,353 4,148 21,113 13,211 Marketing and Specialties Total sales 21,184 11,038 53,286 32,780 Intersegment eliminations (569) (278) (1,462) (1,068) Total Marketing and Specialties 20,615 10,760 51,824 31,712 Corporate and Other 9 8 21 21 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 * See Note 2—Sales and Other Operating Revenues, for further details on our disaggregated sales and other operating revenues. Income (Loss) Before Income Taxes Midstream $ 629 146 1,017 (232) Chemicals 631 231 1,408 442 Refining (1,126) (1,903) (2,895) (5,042) Marketing and Specialties 545 415 1,311 1,214 Corporate and Other (231) (239) (728) (655) Consolidated income (loss) before income taxes $ 448 (1,350) 113 (4,273) Millions of Dollars September 30 December 31 Total Assets Midstream $ 16,063 15,596 Chemicals 6,446 6,183 Refining 20,576 20,404 Marketing and Specialties 8,782 7,180 Corporate and Other 4,540 5,358 Consolidated total assets $ 56,407 54,721

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Our effective income tax rate for the three and nine months ended September 30, 2021, was (9)% and (97)%, respectively, compared with 46% and 25%, respectively, for the corresponding periods of 2020. The decrease in our effective tax rate for the three and nine months ended September 30, 2021, was primarily attributable to the discrete tax treatment of the Alliance Refinery impairment. The tax consequences of the impairment were not included in our estimated annual effective rate but instead were fully reported in the third quarter of 2021. The effective income tax rate for the three months ended September 30, 2021, varied from the U.S. federal statutory income tax rate of 21%, primarily due to the discrete tax treatment of the Alliance Refinery impairment, income attributable to noncontrolling interests, and foreign operations, partially offset by state income tax. The effective income tax rate for the nine months ended September 30, 2021, varied from the U.S. federal statutory income tax rate of 21%, primarily due to the discrete tax treatment of the Alliance Refinery impairment, income attributable to noncontrolling interests, foreign operations and enacted income tax rate changes, partially offset by state income tax. We received a U.S. federal income tax refund of $1.1 billion in the second quarter of 2021.

Phillips 66 Partners LP

Phillips 66 Partners LP	9 Months Ended
	Sep. 30, 2021
Limited Liability Company or Limited Partnership, Business Organization and Operations [Abstract]
Phillips 66 Partners LP	Phillips 66 Partners LP Phillips 66 Partners, headquartered in Houston, Texas, is a publicly traded MLP formed in 2013 to own, operate, develop and acquire primarily fee-based midstream assets. Phillips 66 Partners’ operations currently consist of crude oil, refined petroleum product and NGL transportation, fractionation, processing, terminaling, and storage assets. We consolidate Phillips 66 Partners because we determined it is a VIE of which we are the primary beneficiary. As general partner of Phillips 66 Partners, we have the ability to control its financial interests, as well as the ability to direct the activities that most significantly impact its economic performance. As a result of this consolidation, the public common and perpetual convertible preferred unitholders’ ownership interests in Phillips 66 Partners are reflected as noncontrolling interests in our financial statements. In June 2021, Phillips 66 Partners repurchased 368,528 of its outstanding perpetual convertible preferred units for $24 million in cash. Upon the repurchase, these preferred units were canceled and are no longer outstanding. At September 30, 2021, we owned 170 million Phillips 66 Partners common units, representing a 74% limited partner interest in Phillips 66 Partners, while the public owned a 26% limited partner interest and 13.5 million perpetual convertible preferred units. The most significant assets of Phillips 66 Partners that are available to settle only its obligations, along with its most significant liabilities for which its creditors do not have recourse to Phillips 66’s general credit, were: Millions of Dollars September 30 December 31 Equity investments* $ 2,941 3,244 Net properties, plants and equipment 3,693 3,639 Short-term debt 450 465 Long-term debt 3,446 3,444 * Included in the “Investments and long-term receivables” line item on the Phillips 66 consolidated balance sheet. 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, Texas, and the Sweeny area, including our Sweeny Refinery. Phillips 66 Partners has a consolidated holding company that owns 65% of Gray Oak Pipeline, LLC. In December 2018, a third party acquired 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 operations. 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. Phillips 66 Partners’ effective ownership interest in Gray Oak Pipeline, LLC is 42.25%, after considering the co-venturer’s 35% interest in the consolidated holding company. See Note 5—Investments, Loans and Long-Term Receivables, for further discussion regarding Phillips 66 Partners’ investments in Dakota Access and ETCO, and Liberty. Pending Merger On October 26, 2021, we entered into a definitive merger agreement with Phillips 66 Partners to acquire all of the publicly held common units representing limited partner interests in Phillips 66 Partners not already owned by us on the closing date of the transaction. The agreement provides for an all-stock transaction in which each outstanding Phillips 66 Partners common unitholder would receive 0.50 shares of Phillips 66 common stock for each Phillips 66 Partners common unit. Phillips 66 Partners’ perpetual convertible preferred units will be converted into common units at a premium to the original issuance price prior to exchange for Phillips 66 common stock. This merger is expected to close in the first quarter of 2022, subject to customary closing conditions. Based on the closing market prices of Phillips 66 common stock and Phillips 66 Partners common units on October 26, 2021, we currently expect to issue approximately 42 million shares of our common stock with a value of approximately $3.4 billion on the closing date of this transaction. The number of shares of common stock we will issue and the value of those shares are subject to change until the merger is closed. Upon closing, Phillips 66 Partners will become a wholly owned subsidiary of Phillips 66 and will no longer be a publicly traded partnership. This transaction will be accounted for as an equity transaction and after the closing we will no longer reflect the ownership interest previously held by Phillips 66 Partners’ publicly held common and perpetual convertible preferred unitholders as a noncontrolling interest on our consolidated balance sheet nor will we attribute a portion of Phillips 66 Partners’ net income to these former unitholders on our consolidated statement of operations.

Earnings (Loss) Per Share (Poli

Earnings (Loss) Per Share (Policies)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share The numerator of basic earnings (loss) per share (EPS) is net income (loss) attributable to Phillips 66, adjusted for noncancelable dividends paid on unvested share-based employee awards during the vesting period (participating securities) and the premium paid for the repurchase of noncontrolling interests. The denominator of basic EPS is the sum of the daily weighted-average number of common shares outstanding during the periods presented and fully vested stock and unit awards that have not yet been issued as common stock. The numerator of diluted EPS is also based on net income (loss) attributable to Phillips 66, which is reduced by dividend equivalents paid on participating securities for which the dividends are more dilutive than the participation of the awards in the earnings (loss) of the periods presented, and the premium paid for the repurchase of noncontrolling interests. To the extent unvested stock, unit or option awards and vested unexercised stock options are dilutive, they are included with the weighted-average common shares outstanding in the denominator. Treasury stock is excluded from the denominator in both basic and diluted EPS.
Contingencies and Commitments	A number of lawsuits involving a variety of claims that arose in the ordinary course of business have been filed against us or are subject to indemnifications provided by 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 active and inactive sites. We regularly assess the need for financial 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.
Recurring Fair Value Measurements	Recurring Fair Value Measurements We carry certain assets and liabilities at fair value, which we measure at the reporting date using the price that would be received to sell an asset or paid to transfer a liability (i.e., an exit price), and disclose the quality of these fair values based on the valuation inputs used in these measurements under the following hierarchy: • Level 1: Fair value measured with unadjusted quoted prices from an active market for identical assets or liabilities. • Level 2: Fair value measured either with: (1) adjusted quoted prices from an active market for similar assets or liabilities; or (2) other valuation inputs that are directly or indirectly observable. • Level 3: Fair value measured with unobservable inputs that are significant to the measurement. We classify the fair value of an asset or liability based on the significance of its observable or unobservable inputs to the measurement. However, the fair value of an asset or liability initially reported as Level 3 will be subsequently reported as Level 2 if the unobservable inputs become inconsequential to its measurement or corroborating market data becomes available. Conversely, an asset or liability initially reported as Level 2 will be subsequently reported as Level 3 if corroborating market data becomes unavailable. We used the following methods and assumptions to estimate the fair value of financial instruments: • Cash and cash equivalents —The carrying amount reported on our consolidated balance sheet approximates fair value. • Accounts and notes receivable —The carrying amount reported on our consolidated balance sheet approximates fair value. • Derivative instruments —We fair value our exchange-traded contracts based on quoted market prices obtained from the New York Mercantile Exchange, the Intercontinental Exchange or other exchanges, and classify them as Level 1 in the fair value hierarchy. When exchange-cleared contracts lack sufficient liquidity, or are valued using either adjusted exchange-provided prices or nonexchange quotes, we classify those contracts as Level 2. Physical commodity forward purchase and sales contracts and over-the-counter (OTC) financial swaps are generally valued using forward quotes provided by brokers and price index developers, such as Platts and Oil Price Information Service. We corroborate these quotes with market data and classify the resulting fair values as Level 2. When forward market prices are not available, we estimate fair value using the forward price of a similar commodity, adjusted for the difference in quality or location. In certain less liquid markets or for longer-term contracts, forward prices are not as readily available. In these circumstances, physical commodity purchase and sales contracts and OTC swaps are valued using internally developed methodologies that consider historical relationships among various commodities that result in management’s best estimate of fair value. We classify these contracts as Level 3. Physical and OTC commodity options are valued using industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and contractual prices for the underlying instruments, as well as other relevant economic measures. The degree to which these inputs are observable in the forward markets determines whether the options are classified as Level 2 or 3. We use a midmarket pricing convention (the midpoint between bid and ask prices). When appropriate, valuations are adjusted to reflect credit considerations, generally based on available market evidence. We determine the fair value of our interest rate swaps based on observable market valuations for interest rate swaps that have notional amounts, terms and pay and reset frequencies similar to ours. • Rabbi trust assets —These deferred compensation investments are measured at fair value using unadjusted quoted prices available from national securities exchanges and are therefore categorized as Level 1 in the fair value hierarchy. • Investment in NOVONIX —Our investment in NOVONIX is measured at fair value using unadjusted quoted prices available from Australian Securities Exchange and is therefore categorized as Level 1 in the fair value hierarchy. • Debt —The carrying amount of our floating-rate debt approximates fair value. The fair value of our fixed-rate debt is estimated based on observable market prices.

Sales and Other Operating Rev_2

Sales and Other Operating Revenues (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	The following tables present our disaggregated sales and other operating revenues: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Product Line and Services Refined petroleum products $ 24,838 12,573 63,057 37,431 Crude oil resales 3,091 2,198 9,484 6,565 Natural gas liquids (NGL) 2,331 966 6,048 2,645 Services and other * (17) 192 283 1,079 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 Geographic Location** United States $ 24,011 12,125 61,920 36,212 United Kingdom 2,948 1,850 8,070 5,131 Germany 1,194 805 3,049 2,276 Other foreign countries 2,090 1,149 5,833 4,101 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 * Includes derivatives-related activities. See Note 12—Derivatives and Financial Instruments, for additional information. ** Sales and other operating revenues are attributable to countries based on the location of the operations generating the revenues.

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consisted of the following: Millions of Dollars September 30 December 31 Crude oil and petroleum products $ 4,015 3,536 Materials and supplies 385 357 $ 4,400 3,893

Properties, Plants and Equipm_2

Properties, Plants and Equipment (Tables)	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Schedule of Properties, Plants and Equipment with Associated Accumulated Depreciation and Amortization	Our gross investment in properties, plants and equipment (PP&E) and the associated accumulated depreciation and amortization (Accum. D&A) balances were as follows: Millions of Dollars September 30, 2021 December 31, 2020 Gross Accum. Net Gross Accum. Net Midstream $ 12,435 2,975 9,460 12,313 2,815 9,498 Chemicals — — — — — — Refining 25,378 14,033 11,345 24,647 12,019 12,628 Marketing and Specialties 1,802 1,028 774 1,815 1,007 808 Corporate and Other 1,524 726 798 1,448 666 782 $ 41,139 18,762 22,377 40,223 16,507 23,716

Impairments (Tables)

Impairments (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Impairments	Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Midstream $ 10 204 208 1,365 Refining 1,288 911 1,288 2,756 Corporate and Other — 25 — 25 Total impairments $ 1,298 1,140 1,496 4,146

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Reconciliation of Basic and Diluted Earnings Per Share	Three Months Ended Nine Months Ended 2021 2020 2021 2020 Basic Diluted Basic Diluted Basic Diluted Basic Diluted Amounts Attributed to Phillips 66 Common Stockholders (millions) : Net income (loss) attributable to Phillips 66 $ 402 402 (799) (799) 44 44 (3,436) (3,436) Income allocated to participating securities (2) (2) (2) (2) (7) (7) (6) (6) Premium paid for the repurchase of noncontrolling interests — — — — (2) (2) — — Net income (loss) available to common stockholders $ 400 400 (801) (801) 35 35 (3,442) (3,442) Weighted-average common shares outstanding (thousands) : 438,067 440,193 436,783 438,916 437,783 439,880 437,492 439,670 Effect of share-based compensation 2,126 175 2,133 — 2,097 379 2,178 — Weighted-average common shares outstanding—EPS 440,193 440,368 438,916 438,916 439,880 440,259 439,670 439,670 Earnings (Loss) Per Share of Common Stock (dollars) $ 0.91 0.91 (1.82) (1.82) 0.08 0.08 (7.83) (7.83)

Derivatives and Financial Ins_2

Derivatives and Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Offsetting Liabilities	The following table indicates the consolidated balance sheet line items that include the fair values of commodity derivative assets and liabilities. The balances in the following table are presented on a gross basis, before the effects of counterparty and collateral netting. However, we have elected to present our commodity derivative assets and liabilities with the same counterparty on a net basis on our consolidated balance sheet when the legal right of offset exists. Millions of Dollars September 30, 2021 December 31, 2020 Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Assets Liabilities Assets Liabilities Assets Prepaid expenses and other current assets $ 38 (2) (4) 32 13 — — 13 Other assets 15 (5) — 10 5 (4) — 1 Liabilities Other accruals 1,990 (2,194) 145 (59) 665 (721) 46 (10) Other liabilities and deferred credits 4 (6) — (2) — — — — Total $ 2,047 (2,207) 141 (19) 683 (725) 46 4
Offsetting Assets	The following table indicates the consolidated balance sheet line items that include the fair values of commodity derivative assets and liabilities. The balances in the following table are presented on a gross basis, before the effects of counterparty and collateral netting. However, we have elected to present our commodity derivative assets and liabilities with the same counterparty on a net basis on our consolidated balance sheet when the legal right of offset exists. Millions of Dollars September 30, 2021 December 31, 2020 Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Commodity Derivatives Effect of Collateral Netting Net Carrying Value Presented on the Balance Sheet Assets Liabilities Assets Liabilities Assets Prepaid expenses and other current assets $ 38 (2) (4) 32 13 — — 13 Other assets 15 (5) — 10 5 (4) — 1 Liabilities Other accruals 1,990 (2,194) 145 (59) 665 (721) 46 (10) Other liabilities and deferred credits 4 (6) — (2) — — — — Total $ 2,047 (2,207) 141 (19) 683 (725) 46 4
Summary of Fair Value of Commodity Derivative Assets and Liabilities and Gains (Losses) from Derivative Contracts	The realized and unrealized gains (losses) incurred from commodity derivatives, and the line items where they appear on our consolidated statement of operations, were: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Sales and other operating revenues $ (214) 20 (530) 519 Other income 11 — 30 9 Purchased crude oil and products 66 (16) (282) 301 Net gain (loss) from commodity derivative activity $ (137) 4 (782) 829
Summary of Material Net Exposures and Notional Amount of Derivative Contracts	The following table summarizes our material net exposures resulting from outstanding commodity derivative contracts. These financial and physical derivative contracts are primarily used to manage price exposure on our underlying operations. The underlying exposures may be from nonderivative positions such as inventory volumes. Financial derivative contracts may also offset physical derivative contracts, such as forward purchase and sales contracts. The percentage of our derivative contract volumes expiring within the next 12 months was more than 95% at September 30, 2021, and December 31, 2020. Open Position September 30 December 31 Commodity Crude oil, refined petroleum products, NGL and renewable feedstocks (millions of barrels) (32) (13)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value Hierarchy for Material Financial Instruments and Derivative Assets and Liabilities, Including the Effect of Counterparty Netting	The carrying values and fair values by hierarchy of our financial assets and liabilities, either carried or disclosed at fair value, including any effects of counterparty and collateral netting, were: Millions of Dollars September 30, 2021 Fair Value Hierarchy Total Fair Value of Gross Assets & Liabilities Effect of Counterparty Netting Effect of Collateral Netting Difference in Carrying Value and Fair Value Net Carrying Value Presented on the Balance Sheet Level 1 Level 2 Level 3 Commodity Derivative Assets Exchange-cleared instruments $ 1,093 923 — 2,016 (2,001) (4) — 11 Physical forward contracts — 31 — 31 — — — 31 Rabbi trust assets 152 — — 152 N/A N/A — 152 Investment in NOVONIX 374 — — 374 N/A N/A — 374 $ 1,619 954 — 2,573 (2,001) (4) — 568 Commodity Derivative Liabilities Exchange-cleared instruments $ 1,227 919 — 2,146 (2,001) (145) — — Physical forward contracts — 61 — 61 — — — 61 Floating-rate debt — 925 — 925 N/A N/A — 925 Fixed-rate debt, excluding finance leases — 15,416 — 15,416 N/A N/A (1,736) 13,680 $ 1,227 17,321 — 18,548 (2,001) (145) (1,736) 14,666 Millions of Dollars December 31, 2020 Fair Value Hierarchy Total Fair Value of Gross Assets & Liabilities Effect of Counterparty Netting Effect of Collateral Netting Difference in Carrying Value and Fair Value Net Carrying Value Presented on the Balance Sheet Level 1 Level 2 Level 3 Commodity Derivative Assets Exchange-cleared instruments $ 314 356 — 670 (669) — — 1 Physical forward contracts — 13 — 13 — — — 13 Rabbi trust assets 143 — — 143 N/A N/A — 143 $ 457 369 — 826 (669) — — 157 Commodity Derivative Liabilities Exchange-cleared instruments $ 351 364 — 715 (669) (46) — — Physical forward contracts — 10 — 10 — — — 10 Interest-rate derivatives — 3 — 3 — — — 3 Floating-rate debt — 1,940 — 1,940 N/A N/A — 1,940 Fixed-rate debt, excluding finance leases — 15,597 — 15,597 N/A N/A (1,927) 13,670 $ 351 17,914 — 18,265 (669) (46) (1,927) 15,623

Pension and Postretirement Pl_2

Pension and Postretirement Plans (Tables)	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Schedule of Components of Net Periodic Benefit Cost	The components of net periodic benefit cost for the three and nine months ended September 30, 2021 and 2020, were as follows: Millions of Dollars Pension Benefits Other Benefits 2021 2020 2021 2020 U.S. Int’l. U.S. Int’l. Components of Net Periodic Benefit Cost Three Months Ended September 30 Service cost $ 37 9 35 7 1 1 Interest cost 20 5 21 5 2 2 Expected return on plan assets (39) (15) (38) (12) — — Amortization of prior service credit — — — — (1) (1) Recognized net actuarial loss 8 7 21 4 — — Settlements 18 — 17 — — — Net periodic benefit cost* $ 44 6 56 4 2 2 Nine Months Ended September 30 Service cost $ 111 26 102 21 4 4 Interest cost 60 14 70 16 4 5 Expected return on plan assets (121) (44) (121) (37) — — Amortization of prior service credit — — — — (2) (2) Recognized net actuarial loss (gain) 37 19 50 12 (1) — Settlements 47 — 56 — — — Net periodic benefit cost* $ 134 15 157 12 5 7 * Included in the “Operating expenses” and “Selling, general and administrative expenses” line items on our consolidated statement of operations.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Schedule of Changes in and Reclassifications Out of Accumulated Other Comprehensive Loss by Component	Changes in the balances of each component of accumulated other comprehensive loss were as follows: Millions of Dollars Defined Benefit Plans Foreign Currency Translation Hedging Accumulated Other Comprehensive Loss December 31, 2020 $ (809) 25 (5) (789) Other comprehensive income (loss) before reclassifications 184 (68) 1 117 Amounts reclassified from accumulated other comprehensive loss Defined benefit plans* Amortization of net actuarial loss, prior service credit and settlements 82 — — 82 Foreign currency translation — — — — Hedging — — 1 1 Net current period other comprehensive income (loss) 266 (68) 2 200 September 30, 2021 $ (543) (43) (3) (589) December 31, 2019 $ (656) (131) (1) (788) Other comprehensive loss before reclassifications (221) (44) (8) (273) Amounts reclassified from accumulated other comprehensive loss Defined benefit plans* Amortization of net actuarial loss, prior service credit and settlements 86 — — 86 Foreign currency translation — — — — Hedging — — 3 3 Net current period other comprehensive loss (135) (44) (5) (184) Other — 5 — 5 September 30, 2020 $ (791) (170) (6) (967) * Included in the computation of net periodic benefit cost. See Note 14—Pension and Postretirement Plans, for additional information.

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Schedule of Significant Transactions with Related Parties	Significant transactions with related parties were: Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Operating revenues and other income (a) $ 1,005 450 2,734 1,337 Purchases (b) 3,980 1,612 9,789 4,868 Operating expenses and selling, general and administrative expenses (c) 80 65 215 171 (a) We sold NGL, other petrochemical feedstocks and solvents to Chevron Phillips Chemical Company LLC (CPChem), NGL and certain feedstocks to DCP Midstream, gas oil and hydrogen feedstocks to Excel Paralubes (Excel), and refined petroleum products to several of our equity affiliates in the Marketing and Specialties segment, including OnCue and CF United. We also sold certain feedstocks and intermediate products to WRB and acted as an agent for WRB in supplying crude oil and other feedstocks for a fee. In addition, we charged several of our equity affiliates, including CPChem, for the use of common facilities, such as steam generators, waste and water treaters and warehouse facilities. (b) We purchased crude oil, refined petroleum products, NGL and solvents from WRB. We also purchased natural gas and NGL from DCP Midstream and CPChem, as well as other feedstocks from various equity affiliates, for use in our refinery and fractionation processes. In addition, we purchased base oils and fuel products from Excel for use in our specialty and refining businesses. We paid NGL fractionation fees to CPChem. We also paid fees to various pipeline equity affiliates for transporting crude oil, refined petroleum products and NGL. (c) We paid consignment fees to CF United, and utility and processing fees to various equity affiliates.

Segment Disclosures and Relat_2

Segment Disclosures and Related Information (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Analysis of Results by Operating Segment	Analysis of Results by Operating Segment Millions of Dollars Three Months Ended Nine Months Ended 2021 2020 2021 2020 Sales and Other Operating Revenues * Midstream Total sales $ 3,067 1,458 8,049 4,096 Intersegment eliminations (802) (446) (2,138) (1,323) Total Midstream 2,265 1,012 5,911 2,773 Chemicals 1 1 3 3 Refining Total sales 20,206 10,434 53,939 31,567 Intersegment eliminations (12,853) (6,286) (32,826) (18,356) Total Refining 7,353 4,148 21,113 13,211 Marketing and Specialties Total sales 21,184 11,038 53,286 32,780 Intersegment eliminations (569) (278) (1,462) (1,068) Total Marketing and Specialties 20,615 10,760 51,824 31,712 Corporate and Other 9 8 21 21 Consolidated sales and other operating revenues $ 30,243 15,929 78,872 47,720 * See Note 2—Sales and Other Operating Revenues, for further details on our disaggregated sales and other operating revenues. Income (Loss) Before Income Taxes Midstream $ 629 146 1,017 (232) Chemicals 631 231 1,408 442 Refining (1,126) (1,903) (2,895) (5,042) Marketing and Specialties 545 415 1,311 1,214 Corporate and Other (231) (239) (728) (655) Consolidated income (loss) before income taxes $ 448 (1,350) 113 (4,273)
Schedule of Reconciliation of Assets from Segment to Consolidated	Millions of Dollars September 30 December 31 Total Assets Midstream $ 16,063 15,596 Chemicals 6,446 6,183 Refining 20,576 20,404 Marketing and Specialties 8,782 7,180 Corporate and Other 4,540 5,358 Consolidated total assets $ 56,407 54,721

Phillips 66 Partners LP (Tables

Phillips 66 Partners LP (Tables)	9 Months Ended
	Sep. 30, 2021
Limited Liability Company or Limited Partnership, Business Organization and Operations [Abstract]
Schedule of Variable Interest Entities	The most significant assets of Phillips 66 Partners that are available to settle only its obligations, along with its most significant liabilities for which its creditors do not have recourse to Phillips 66’s general credit, were: Millions of Dollars September 30 December 31 Equity investments* $ 2,941 3,244 Net properties, plants and equipment 3,693 3,639 Short-term debt 450 465 Long-term debt 3,446 3,444 * Included in the “Investments and long-term receivables” line item on the Phillips 66 consolidated balance sheet.

Sales and Other Operating Rev_3

Sales and Other Operating Revenues - Disaggregated (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	$ 30,243	$ 15,929	$ 78,872	$ 47,720
United States
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	24,011	12,125	61,920	36,212
United Kingdom
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	2,948	1,850	8,070	5,131
Germany
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	1,194	805	3,049	2,276
Other foreign countries
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	2,090	1,149	5,833	4,101
Refined petroleum products
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	24,838	12,573	63,057	37,431
Crude oil resales
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	3,091	2,198	9,484	6,565
Natural gas liquids (NGL)
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	2,331	966	6,048	2,645
Services and other
Disaggregation of Revenue [Line Items]
Sales and other operating revenues	$ (17)	$ 192	$ 283	$ 1,079

Sales and Other Operating Rev_4

Sales and Other Operating Revenues - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable	$ 6,341	$ 3,911
Receivables from contracts with customers	$ 435	$ 404
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

Credit Losses (Details)

Credit Losses (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Credit Loss [Abstract]
Accounts and notes receivable	$ 8,006	$ 6,522
Allowance for credit losses	$ 36	$ 37
Accounts and notes receivable, percent outstanding less than 60 days (more than)	95.00%

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Crude oil and petroleum products	$ 4,015	$ 3,536
Materials and supplies	385	357
Inventories	$ 4,400	$ 3,893

Inventories - Narrative (Detail

Inventories - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
LIFO inventory amount	$ 3,828	$ 3,828	$ 3,368
Estimated excess of current replacement cost over LIFO cost of inventories	6,100	6,100	$ 2,700
Increase (decrease) on net income (loss) from LIFO inventory liquidations	$ (17)	$ (99)

Investments, Loans and Long-T_2

Investments, Loans and Long-Term Receivables - Dakota Access, LLC and Energy Transfer Crude Oil, Company, LLC (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Sep. 30, 2021	Dec. 31, 2020	Jun. 10, 2020	Apr. 09, 2020
Dakota Access, LLC | Forecast
Schedule of Equity Method Investments [Line Items]
Scheduled interest payments annually	$ 25,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary
Schedule of Equity Method Investments [Line Items]
Equity investments		$ 2,941,000,000	$ 3,244,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Dakota Access and ETCO
Schedule of Equity Method Investments [Line Items]
Maximum exposure, undiscounted		631,000,000
Equity investments		579,000,000
Senior Notes
Schedule of Equity Method Investments [Line Items]
Debt issued and guaranteed				$ 1,000,000,000	$ 1,000,000,000
Senior Notes | Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Debt issued and guaranteed		$ 2,500,000,000

Investments, Loans and Long-T_3

Investments, Loans and Long-Term Receivables - CF United LLC (Details) - CF United LLC $ in Millions	Sep. 30, 2021USD ($)
Schedule of Equity Method Investments [Line Items]
Voting interest acquired	50.00%
Economic interest acquired	48.00%
Equity investments	$ 271

Investments, Loans and Long-T_4

Investments, Loans and Long-Term Receivables - OnCue Holdings, LLC (Details) - OnCue Holdings, LLC $ in Millions	Sep. 30, 2021USD ($)
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest	50.00%
Maximum loss exposure	$ 183
Equity investments	113
Maximum potential amount of future payments under the guarantees	$ 70

Investments, Loans and Long-T_5

Investments, Loans and Long-Term Receivables - Liberty Pipeline LLC (Liberty) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Impairments	$ 1,298		$ 1,140	$ 1,496	$ 4,146
Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP
Schedule of Equity Method Investments [Line Items]
Equity investments	$ 2,941			$ 2,941		$ 3,244
Liberty Pipeline LLC | Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP
Schedule of Equity Method Investments [Line Items]
Impairments		$ 198
Equity investments		$ 46

Investments, Loans and Long-T_6

Investments, Loans and Long-Term Receivables - Other Investments (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Debt and Equity Securities, FV-NI [Line Items]
Unrealized gain (loss) on equity securities			$ 224	$ 0
NOVONIX Limited
Debt and Equity Securities, FV-NI [Line Items]
Shares acquired (in shares)	78
Percent stake acquired	16.00%
Payments to acquire equity securities	$ 150
Equity securities	$ 374	$ 374	374
Unrealized gain (loss) on equity securities		$ 224	$ 224

Investments, Loans and Long-T_7

Investments, Loans and Long-Term Receivables - Related Party Loan (Details) - WRB Refining LP $ in Millions	Sep. 30, 2021USD ($)
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest	50.00%
Outstanding related party loan balance	$ 593

Properties, Plants and Equipm_3

Properties, Plants and Equipment (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Gross PP&E	$ 41,139	$ 40,223
Accum. D&A	18,762	16,507
Net PP&E	22,377	23,716
Corporate and Other
Property, Plant and Equipment [Line Items]
Gross PP&E	1,524	1,448
Accum. D&A	726	666
Net PP&E	798	782
Midstream | Operating Segments
Property, Plant and Equipment [Line Items]
Gross PP&E	12,435	12,313
Accum. D&A	2,975	2,815
Net PP&E	9,460	9,498
Chemicals | Operating Segments
Property, Plant and Equipment [Line Items]
Gross PP&E	0	0
Accum. D&A	0	0
Net PP&E	0	0
Refining | Operating Segments
Property, Plant and Equipment [Line Items]
Gross PP&E	25,378	24,647
Accum. D&A	14,033	12,019
Net PP&E	11,345	12,628
Marketing and Specialties | Operating Segments
Property, Plant and Equipment [Line Items]
Gross PP&E	1,802	1,815
Accum. D&A	1,028	1,007
Net PP&E	$ 774	$ 808

Impairments - Schedule of Impai

Impairments - Schedule of Impairments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Goodwill [Line Items]
Impairments	$ 1,298	$ 1,140	$ 1,496	$ 4,146
Operating Segments | Midstream
Goodwill [Line Items]
Impairments	10	204	208	1,365
Operating Segments | Refining
Goodwill [Line Items]
Impairments	1,288	911	1,288	2,756
Corporate and Other
Goodwill [Line Items]
Impairments	$ 0	$ 25	$ 0	$ 25

Impairments - Narrative (Detail

Impairments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Goodwill [Line Items]
Impairments	$ 1,298		$ 1,140		$ 1,496	$ 4,146
Alliance Refinery
Goodwill [Line Items]
Impairments	1,298
Fair value of PP&E	200				$ 200
San Francisco Refinery Asset Group
Goodwill [Line Items]
Impairments			1,030
Fair value of PP&E			940			$ 940
PP&E			1,009
Refining
Goodwill [Line Items]
Goodwill				$ 1,845
Refining | Alliance Refinery
Goodwill [Line Items]
Impairments	1,288
Refining | San Francisco Refinery Asset Group
Goodwill [Line Items]
Intangible assets			21
Midstream | Alliance Refinery
Goodwill [Line Items]
Impairments	$ 10
Midstream | San Francisco Refinery Asset Group
Goodwill [Line Items]
PP&E			120
Liberty Pipeline LLC | Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP
Goodwill [Line Items]
Impairments		$ 198
Red Oak Pipeline LLC
Goodwill [Line Items]
Equity method investment impairment			84
Equity investments			$ 84
DCP Midstream, LLC
Goodwill [Line Items]
Equity method investment impairment				1,161
Equity investments				$ 1,161
DCP Midstream, LLC | DCP Partners
Goodwill [Line Items]
Equity method investment, decline in market value, percent				85.00%

Earnings (Loss) Per Share - Sum

Earnings (Loss) Per Share - Summary of Earnings Per Share Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Basic
Net income (loss) attributable to Phillips 66	$ 402	$ (799)	$ 44	$ (3,436)
Income allocated to participating securities	(2)	(2)	(7)	(6)
Net income (loss) available to common stockholders	$ 400	$ (801)	$ 35	$ (3,442)
Weighted-average common shares outstanding (in shares)	438,067	436,783	437,783	437,492
Effect of share-based compensation (in shares)	2,126	2,133	2,097	2,178
Weighted-average commons shares outstanding - EPS (in shares)	440,193	438,916	439,880	439,670
Earnings (Loss) Per Share of Common Stock (in usd per share)	$ 0.91	$ (1.82)	$ 0.08	$ (7.83)
Diluted
Net income (loss) attributable to Phillips 66	$ 402	$ (799)	$ 44	$ (3,436)
Income allocated to participating securities	(2)	(2)	(7)	(6)
Net income (loss) available to common stockholders	$ 400	$ (801)	$ 35	$ (3,442)
Weighted-average common shares outstanding (in shares)	440,193	438,916	439,880	439,670
Effect of share-based compensation (in shares)	175	0	379	0
Weighted-average commons shares outstanding - EPS (in shares)	440,368	438,916	440,259	439,670
Earnings (Loss) Per Share of Common Stock (in usd per share)	$ 0.91	$ (1.82)	$ 0.08	$ (7.83)
Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP
Basic
Premium paid for the repurchase of noncontrolling interests	$ 0	$ 0	$ (2)	$ 0
Diluted
Premium paid for the repurchase of noncontrolling interests	$ 0	$ 0	$ (2)	$ 0

Debt (Details)

Debt (Details) - USD ($)	Jun. 10, 2020	Apr. 09, 2020	Mar. 19, 2020	Sep. 30, 2021	Apr. 30, 2021	Feb. 28, 2021	Nov. 30, 2020	Apr. 30, 2020	Dec. 31, 2020	Apr. 06, 2020
Debt Instrument [Line Items]
Long-term debt due within a year				$ 1,000,000,000
Line of Credit | Long-term debt
Debt Instrument [Line Items]
Repayments of debt				500,000,000
Amount borrowed							$ 500,000,000
Line of Credit | Term Loan
Debt Instrument [Line Items]
Repayments of debt							$ 500,000,000
Line of credit facility, maximum borrowing capacity			$ 1,000,000,000							$ 2,000,000,000
Proceeds from borrowings			$ 1,000,000,000
Delayed term			364 days
Loans Payable | Floating Rate Senior Note Notes Due February 2021
Debt Instrument [Line Items]
Repayments of debt						$ 500,000,000
Loans Payable | Floating Rate Notes Due April 2020
Debt Instrument [Line Items]
Repayments of debt								$ 300,000,000
Loans Payable | Term Loan Due April 2020
Debt Instrument [Line Items]
Repayments of debt								200,000,000
Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed	$ 1,000,000,000	$ 1,000,000,000
Senior Notes | 3.850% Senior Notes due April 9, 2025
Debt Instrument [Line Items]
Debt issued and guaranteed	$ 650,000,000	$ 650,000,000
Debt interest rate	3.85%	3.85%
Senior Notes | 3.850% Senior Notes Due April 9, 2025, Portion Issued June 10, 2020
Debt Instrument [Line Items]
Debt issued and guaranteed	$ 150,000,000
Senior Notes | 3.850% Senior Notes Due April 9, 2025, Portion Issued April 9, 2020
Debt Instrument [Line Items]
Debt issued and guaranteed		$ 500,000,000
Senior Notes | 2.150% Senior Notes Due 2030
Debt Instrument [Line Items]
Debt issued and guaranteed	$ 850,000,000
Debt interest rate	2.15%
Senior Notes | 3.700% Senior Notes Due 2023
Debt Instrument [Line Items]
Debt issued and guaranteed		$ 500,000,000
Debt interest rate		3.70%
Senior Notes | Senior Unsecured Notes
Debt Instrument [Line Items]
Proceeds from borrowings	$ 1,008,000,000	$ 993,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity				750,000,000
Amount borrowed				0					$ 415,000,000
Letters of credit and bank guarantees				$ 1,000,000					$ 1,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Line of Credit | Term Loan
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					$ 450,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Line of Credit | Term Loan | Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate					0.875%
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Line of Credit | Term Loan | Reference Rate
Debt Instrument [Line Items]
Basis spread on variable rate					0.875%
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Tax-Exempt Bonds | Tax Exempt Bonds Due 2021
Debt Instrument [Line Items]
Repayments of debt					$ 50,000,000
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Tax-Exempt Bonds | Tax Exempt Bonds Due April 2020
Debt Instrument [Line Items]
Repayments of debt								$ 25,000,000

Guarantees (Details)

Guarantees (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Guarantor Obligations [Line Items]
Environmental accruals included in recorded carrying amount	$ 453	$ 427
Other Guarantees | Other joint ventures and entities
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	$ 122
Joint venture debt obligations, period (up to)	4 years
Indemnifications
Guarantor Obligations [Line Items]
Carrying amount of indemnifications	$ 146	145
Indemnifications | Asset Retirement Obligations And Accrued Environmental Cost
Guarantor Obligations [Line Items]
Environmental accruals included in recorded carrying amount	108	$ 104
Facilities | Residual Value Guarantees
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	514
Railcar and Airplane | Residual Value Guarantees
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	$ 209
Lessee operating lease remaining lease term (up to)	10 years

Contingencies and Commitments (

Contingencies and Commitments (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total environmental accrual	$ 453	$ 427
Expected period to incur a substantial amount of expenditures	30 years
Performance Guarantee
Debt Instrument [Line Items]
Letters of credit and bank guarantees	$ 740

Derivatives and Financial Ins_3

Derivatives and Financial Instruments - Summary of Commodity Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Liabilities	$ (2,001)	$ (669)
Effect of Collateral Netting	(4)	0
Liabilities
Assets	2,001	669
Effect of Collateral Netting	145	46
Total
Effect of Collateral Netting	145	46
Not Designated as Hedging Instrument | Commodity
Liabilities
Effect of Collateral Netting	141	46
Total
Assets	2,047	683
Liabilities	(2,207)	(725)
Effect of Collateral Netting	141	46
Net Carrying Value Presented on the Balance Sheet	(19)	4
Not Designated as Hedging Instrument | Commodity | Prepaid expenses and other current assets
Assets
Assets	38	13
Liabilities	(2)	0
Effect of Collateral Netting	(4)	0
Net Carrying Value Presented on the Balance Sheet	32	13
Not Designated as Hedging Instrument | Commodity | Other assets
Assets
Assets	15	5
Liabilities	(5)	(4)
Effect of Collateral Netting	0	0
Net Carrying Value Presented on the Balance Sheet	10	1
Not Designated as Hedging Instrument | Commodity | Other accruals
Liabilities
Assets	1,990	665
Liabilities	(2,194)	(721)
Effect of Collateral Netting	145	46
Net Carrying Value Presented on the Balance Sheet	(59)	(10)
Total
Effect of Collateral Netting	145	46
Not Designated as Hedging Instrument | Commodity | Other liabilities and deferred credits
Liabilities
Assets	4	0
Liabilities	(6)	0
Effect of Collateral Netting	0	0
Net Carrying Value Presented on the Balance Sheet	(2)	0
Total
Effect of Collateral Netting	$ 0	$ 0

Derivatives and Financial Ins_4

Derivatives and Financial Instruments - Summary of Gains/(Losses) From Commodity Derivatives (Details) - Commodity Derivative Assets - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) from commodity derivative activity	$ (137)	$ 4	$ (782)	$ 829
Sales and other operating revenues
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) from commodity derivative activity	(214)	20	(530)	519
Other income
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) from commodity derivative activity	11	0	30	9
Purchased crude oil and products
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) from commodity derivative activity	$ 66	$ (16)	$ (282)	$ 301

Derivatives and Financial Ins_5

Derivatives and Financial Instruments - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Apr. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Percentage of derivative contract volume expiring within twelve months (at least)	95.00%		95.00%
Cash Flow Hedging | Interest rate derivatives
Derivative [Line Items]
Derivative, notional amount		$ 650

Derivatives and Financial Ins_6

Derivatives and Financial Instruments - Summary of Outstanding Commodity Derivative Contracts (Details) - bbl bbl in Millions	Sep. 30, 2021	Dec. 31, 2020
Short | Commodity Derivative Assets
Derivative [Line Items]
Crude oil, refined petroleum products, NGL and renewable feedstocks (in barrels)	(32)	(13)

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Fair Value of Derivative Assets and Liabilities and Effect of Counterparty Netting (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Total Fair Value of Gross Assets	$ 2,573	$ 826
Effect of Counterparty Netting	(2,001)	(669)
Effect of Collateral Netting	(4)	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	568	157
Liabilities
Total Fair Value Gross Liabilities	18,548	18,265
Effect of Counterparty Netting	(2,001)	(669)
Effect of Collateral Netting	(145)	(46)
Difference in Carrying Value and Fair Value	(1,736)	(1,927)
Net Carrying Value Presented on the Balance Sheet	14,666	15,623
Level 1
Assets
Total Fair Value of Gross Assets	1,619	457
Liabilities
Total Fair Value Gross Liabilities	1,227	351
Level 2
Assets
Total Fair Value of Gross Assets	954	369
Liabilities
Total Fair Value Gross Liabilities	17,321	17,914
Level 3
Assets
Total Fair Value of Gross Assets	0	0
Liabilities
Total Fair Value Gross Liabilities	0	0
Commodity Derivative Assets | Exchange-cleared instruments
Assets
Commodity Derivative Assets	2,016	670
Effect of Counterparty Netting	(2,001)	(669)
Effect of Collateral Netting	(4)	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	11	1
Liabilities
Commodity Derivative Liabilities	2,146	715
Effect of Counterparty Netting	(2,001)	(669)
Effect of Collateral Netting	(145)	(46)
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	0	0
Commodity Derivative Assets | Physical forward contracts
Assets
Commodity Derivative Assets	31	13
Effect of Counterparty Netting	0	0
Effect of Collateral Netting	0	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	31	13
Liabilities
Commodity Derivative Liabilities	61	10
Effect of Counterparty Netting	0	0
Effect of Collateral Netting	0	0
Difference in Carrying Value and Fair Value	0	0
Net Carrying Value Presented on the Balance Sheet	61	10
Commodity Derivative Assets | Level 1 | Exchange-cleared instruments
Assets
Commodity Derivative Assets	1,093	314
Liabilities
Commodity Derivative Liabilities	1,227	351
Commodity Derivative Assets | Level 1 | Physical forward contracts
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Commodity Derivative Assets | Level 2 | Exchange-cleared instruments
Assets
Commodity Derivative Assets	923	356
Liabilities
Commodity Derivative Liabilities	919	364
Commodity Derivative Assets | Level 2 | Physical forward contracts
Assets
Commodity Derivative Assets	31	13
Liabilities
Commodity Derivative Liabilities	61	10
Commodity Derivative Assets | Level 3 | Exchange-cleared instruments
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Commodity Derivative Assets | Level 3 | Physical forward contracts
Assets
Commodity Derivative Assets	0	0
Liabilities
Commodity Derivative Liabilities	0	0
Rabbi trust assets
Assets
Investments fair value	152	143
Difference in Carrying Value and Fair Value	0	0
Rabbi trust assets | Level 1
Assets
Investments fair value	152	143
Rabbi trust assets | Level 2
Assets
Investments fair value	0	0
Rabbi trust assets | Level 3
Assets
Investments fair value	0	0
Investment in NOVONIX
Assets
Investments fair value	374
Difference in Carrying Value and Fair Value	0
Investment in NOVONIX | Level 1
Assets
Investments fair value	374
Investment in NOVONIX | Level 2
Assets
Investments fair value	0
Investment in NOVONIX | Level 3
Assets
Investments fair value	0
Interest rate derivatives
Liabilities
Commodity Derivative Liabilities		3
Effect of Counterparty Netting		0
Effect of Collateral Netting		0
Difference in Carrying Value and Fair Value		0
Net Carrying Value Presented on the Balance Sheet		3
Interest rate derivatives | Level 1
Liabilities
Commodity Derivative Liabilities		0
Interest rate derivatives | Level 2
Liabilities
Commodity Derivative Liabilities		3
Interest rate derivatives | Level 3
Liabilities
Commodity Derivative Liabilities		0
Floating-rate debt
Liabilities
Debt	925	1,940
Difference in Carrying Value and Fair Value	0	0
Floating-rate debt | Net Carrying Value Presented on the Balance Sheet
Liabilities
Debt	925	1,940
Floating-rate debt | Level 1
Liabilities
Debt	0	0
Floating-rate debt | Level 2
Liabilities
Debt	925	1,940
Floating-rate debt | Level 3
Liabilities
Debt	0	0
Fixed-rate debt, excluding finance leases
Liabilities
Debt	15,416	15,597
Difference in Carrying Value and Fair Value	(1,736)	(1,927)
Fixed-rate debt, excluding finance leases | Net Carrying Value Presented on the Balance Sheet
Liabilities
Debt	13,680	13,670
Fixed-rate debt, excluding finance leases | Level 1
Liabilities
Debt	0	0
Fixed-rate debt, excluding finance leases | Level 2
Liabilities
Debt	15,416	15,597
Fixed-rate debt, excluding finance leases | Level 3
Liabilities
Debt	$ 0	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill	$ 1,425,000,000	$ 1,425,000,000
Refining
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill			$ 0

Pension and Postretirement Pl_3

Pension and Postretirement Plans - Summary of Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Other Benefits
Components of Net Periodic Benefit Cost
Service cost	$ 1	$ 1	$ 4	$ 4
Interest cost	2	2	4	5
Expected return on plan assets	0	0	0	0
Amortization of prior service credit	(1)	(1)	(2)	(2)
Recognized net actuarial loss (gain)	0	0	(1)	0
Settlements	0	0	0	0
Net periodic benefit cost	2	2	5	7
U.S. | Pension Benefits
Components of Net Periodic Benefit Cost
Service cost	37	35	111	102
Interest cost	20	21	60	70
Expected return on plan assets	(39)	(38)	(121)	(121)
Amortization of prior service credit	0	0	0	0
Recognized net actuarial loss (gain)	8	21	37	50
Settlements	18	17	47	56
Net periodic benefit cost	44	56	134	157
Int’l. | Pension Benefits
Components of Net Periodic Benefit Cost
Service cost	9	7	26	21
Interest cost	5	5	14	16
Expected return on plan assets	(15)	(12)	(44)	(37)
Amortization of prior service credit	0	0	0	0
Recognized net actuarial loss (gain)	7	4	19	12
Settlements	0	0	0	0
Net periodic benefit cost	$ 6	$ 4	$ 15	$ 12

Pension and Postretirement Pl_4

Pension and Postretirement Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
U.S.
Defined Benefit Plan Disclosure [Line Items]
Company contributions to plans			$ 37
Additional contributions expected to be made during remainder of fiscal year	$ 16		16
U.S. | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension settlement expense	18	$ 17	47	$ 56
Int’l. | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Company contributions to plans			20
Additional contributions expected to be made during remainder of fiscal year	8		8
Pension settlement expense	$ 0	$ 0	$ 0	$ 0

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 20,602	$ 23,295	$ 21,523	$ 27,169
Other comprehensive income (loss) before reclassifications			117	(273)
Other Comprehensive Income (Loss), Net of Income Taxes	(40)	181	200	(184)
Other				5
Ending balance	20,597	22,305	20,597	22,305
Defined Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(809)	(656)
Other comprehensive income (loss) before reclassifications			184	(221)
Amounts reclassified from accumulated other comprehensive loss			82	86
Other Comprehensive Income (Loss), Net of Income Taxes			266	(135)
Other				0
Ending balance	(543)	(791)	(543)	(791)
Foreign Currency Translation
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			25	(131)
Other comprehensive income (loss) before reclassifications			(68)	(44)
Amounts reclassified from accumulated other comprehensive loss			0	0
Other Comprehensive Income (Loss), Net of Income Taxes			(68)	(44)
Other				5
Ending balance	(43)	(170)	(43)	(170)
Hedging
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(5)	(1)
Other comprehensive income (loss) before reclassifications			1	(8)
Amounts reclassified from accumulated other comprehensive loss			1	3
Other Comprehensive Income (Loss), Net of Income Taxes			2	(5)
Other				0
Ending balance	(3)	(6)	(3)	(6)
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(549)	(1,148)	(789)	(788)
Other Comprehensive Income (Loss), Net of Income Taxes	(40)	181	200	(184)
Ending balance	$ (589)	$ (967)	$ (589)	$ (967)

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Related Party Transactions [Abstract]
Operating revenues and other income	$ 1,005	$ 450	$ 2,734	$ 1,337
Purchases	3,980	1,612	9,789	4,868
Operating expenses and selling, general and administrative expenses	$ 80	$ 65	$ 215	$ 171

Segment Disclosures and Relat_3

Segment Disclosures and Related Information - Narrative (Details)	9 Months Ended
	Sep. 30, 2021refinery
Refining | Mainly United States And Europe
Segment Reporting Information [Line Items]
Number of refineries	13
DCP Midstream, LLC | Midstream
Segment Reporting Information [Line Items]
Percentage of ownership interest	50.00%
CPChem | Chemicals
Segment Reporting Information [Line Items]
Percentage of ownership interest	50.00%

Segment Disclosures and Relat_4

Segment Disclosures and Related Information - Summary of Sales and Other Operating Revenues, Net Income (Loss) Attributable to Phillips 66 and Total Assets by Operating Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Sales and other operating revenues	$ 30,243	$ 15,929	$ 78,872	$ 47,720
Consolidated income (loss) before income taxes	448	(1,350)	113	(4,273)
Total Assets	56,407		56,407		$ 54,721
Midstream
Segment Reporting Information [Line Items]
Sales and other operating revenues	2,265	1,012	5,911	2,773
Refining
Segment Reporting Information [Line Items]
Sales and other operating revenues	7,353	4,148	21,113	13,211
Marketing and Specialties
Segment Reporting Information [Line Items]
Sales and other operating revenues	20,615	10,760	51,824	31,712
Operating Segments | Midstream
Segment Reporting Information [Line Items]
Sales and other operating revenues	3,067	1,458	8,049	4,096
Consolidated income (loss) before income taxes	629	146	1,017	(232)
Total Assets	16,063		16,063		15,596
Operating Segments | Chemicals
Segment Reporting Information [Line Items]
Sales and other operating revenues	1	1	3	3
Consolidated income (loss) before income taxes	631	231	1,408	442
Total Assets	6,446		6,446		6,183
Operating Segments | Refining
Segment Reporting Information [Line Items]
Sales and other operating revenues	20,206	10,434	53,939	31,567
Consolidated income (loss) before income taxes	(1,126)	(1,903)	(2,895)	(5,042)
Total Assets	20,576		20,576		20,404
Operating Segments | Marketing and Specialties
Segment Reporting Information [Line Items]
Sales and other operating revenues	21,184	11,038	53,286	32,780
Consolidated income (loss) before income taxes	545	415	1,311	1,214
Total Assets	8,782		8,782		7,180
Intersegment eliminations | Midstream
Segment Reporting Information [Line Items]
Sales and other operating revenues	(802)	(446)	(2,138)	(1,323)
Intersegment eliminations | Refining
Segment Reporting Information [Line Items]
Sales and other operating revenues	(12,853)	(6,286)	(32,826)	(18,356)
Intersegment eliminations | Marketing and Specialties
Segment Reporting Information [Line Items]
Sales and other operating revenues	(569)	(278)	(1,462)	(1,068)
Corporate and Other
Segment Reporting Information [Line Items]
Sales and other operating revenues	9	8	21	21
Consolidated income (loss) before income taxes	(231)	$ (239)	(728)	$ (655)
Total Assets	$ 4,540		$ 4,540		$ 5,358

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Billions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Effective tax rate, percent	(9.00%)		46.00%	(97.00%)	25.00%
Income tax refunds received		$ 1.1

Phillips 66 Partners LP - Narra

Phillips 66 Partners LP - Narrative (Details) - USD ($) $ in Millions	Oct. 26, 2021	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2018
Subsidiary or Equity Method Investee [Line Items]
Net gain on dispositions				$ 9	$ 1		$ 11	$ 87
Gray Oak Pipeline LLC | Third Party
Subsidiary or Equity Method Investee [Line Items]
Capital spending funded by joint venture partner								$ 64
Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP | Gray Oak Pipeline LLC
Subsidiary or Equity Method Investee [Line Items]
Effective ownership percent		42.25%		42.25%			42.25%
Preferred Units | Phillips 66 Partners LP
Subsidiary or Equity Method Investee [Line Items]
Repurchase of preferred units (in shares)			368,528
Repurchase of preferred units			$ 24
Phillips 66 Partners LP
Subsidiary or Equity Method Investee [Line Items]
Limited partner interest in Phillips 66 Partners owned by public, percentage		26.00%
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary
Subsidiary or Equity Method Investee [Line Items]
Limited partnership interest in Phillips 66 Partners, percentage		74.00%
Phillips 66 Partners LP | Variable Interest Entity, Primary Beneficiary | Subsequent Event | Acquisition Of Phillips 66 Partners Common Units Held By Public
Subsidiary or Equity Method Investee [Line Items]
Number of shares issued per acquiree share (in shares)	0.50
Number of shares to be issued (in shares)	42,000,000
Value of shares to be issued	$ 3,400
Phillips 66 Partners LP | Preferred Units | Variable Interest Entity, Primary Beneficiary
Subsidiary or Equity Method Investee [Line Items]
Ownership interest (in shares)		13,500,000		13,500,000			13,500,000
Phillips 66 Partners LP | Common Units | Variable Interest Entity, Primary Beneficiary
Subsidiary or Equity Method Investee [Line Items]
Ownership interest (in shares)		170,000,000		170,000,000			170,000,000
Gray Oak Holdings LLC | Third Party
Subsidiary or Equity Method Investee [Line Items]
Percentage of ownership		35.00%		35.00%		35.00%	35.00%		35.00%
Net gain on dispositions						$ 84
Gray Oak Holdings LLC | Variable Interest Entity, Primary Beneficiary | Phillips 66 Partners LP | Gray Oak Pipeline LLC
Subsidiary or Equity Method Investee [Line Items]
Percentage of ownership		65.00%		65.00%			65.00%

Phillips 66 Partners LP - Sched

Phillips 66 Partners LP - Schedule of Assets and Liabilities (Details) - Phillips 66 Partners LP - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entity [Line Items]
Equity investments	$ 2,941	$ 3,244
Net properties, plants and equipment	3,693	3,639
Short-term debt	450	465
Long-term debt	$ 3,446	$ 3,444