Assets Acquisitions and Dispositions	12 Months Ended
Assets Acquisitions and Dispositions	Dec. 31, 2020
Disposal Group Not Discontinued Operation Disposal Disclosures [Abstract]
Long Lived Assets Held For Sale [Text Block]	Note 4—Asset Acquisitions and Dispositions All gains or losses on asset dispositions are reported before-tax and are included net in the “Gain on dispositions” line on our consolidated income statement. All cash proceeds and payments are included in the “Cash Flows From Investing Activities” section of our consolidated statement of cash flows. On January 15, 2021, we completed our acquisition of Concho Resources Inc. (Concho), an independent oil and gas exploration and production company with operations across New Mexico and West Texas focused in the Permian Basin. Total consideration for the all-stock transaction was valued at $ 13.1 billion, in which 1.46 shares of ConocoPhillips common stock was exchanged for each outstanding share of Concho common stock, resulting in the issuance of approximately 286 million shares of ConocoPhillips common stock. We also assumed $ 3.9 billion in aggregate principal amount of outstanding debt for Concho, which was recorded at fair value of $ 4.7 billion as of the closing date. For additional information related to this transaction, see Note 25—Acquisition of Concho Resources Inc. 2020 Asset Acquisition In August 2020, we completed the acquisition of additional Montney acreage in Canada from Kelt Exploration Ltd. for $ 382 million after customary adjustments, plus the assumption of $ 31 million in financing obligations associated with partially owned infrastructure. This acquisition consisted primarily of undeveloped properties and included 140,000 net acres in the liquids-rich Inga Fireweed asset Montney zone, which is directly adjacent to our existing Montney position. The transaction increased our Montney acreage position to approximately 295,000 net acres with a 100 percent working interest. This agreement was accounted for as an asset acquisition resulting in the recognition of $ 490 million of PP&E; $ 77 million of ARO and accrued environmental costs; and $ 31 million of financing obligations recorded primarily to long-term debt. Results of operations for the Montney asset are reported in our Canada segment. Assets Sold In February 2020, we sold our Waddell Ranch interests in the Permian Basin for $ 184 million after customary adjustments. No gain or loss was recognized on the sale. Results of operations for the Waddell Ranch interests sold were reported in our Lower 48 segment. In March 2020, we completed the sale of our Niobrara interests for approximately $ 359 million after customary adjustments and recognized a before-tax loss on disposition of $ 38 million. At the time of disposition, our interest in Niobrara had a net carrying value of $ 397 million, consisting primarily of $ 433 million of PP&E and $ 34 million of ARO. The before-tax losses associated with our interests in Niobrara, including the loss on disposition noted above and an impairment of $ 386 million recorded when we signed an agreement to sell our interests in the fourth quarter of 2019, were $ 25 million and $ 372 million for the years ended December 31, 2020 and 2019, respectively. The before-tax earnings associated with our interests in Niobrara for the year ended December 31, 2018 was $ 35 million. Results of operations for the Niobrara interests sold were reported in our Lower 48 segment. In May 2020, we completed the divestiture of our subsidiaries that held our Australia-West assets and operations, and based on an effective date of January 1, 2019, we received proceeds of $ 765 million with an additional $ 200 million due upon final investment decision of the proposed Barossa development project. We recognized a before-tax gain of $ 587 million related to this transaction in 2020. At the time of disposition, the net carrying value of the subsidiaries sold was approximately $ 0.2 billion, excluding $ 0.5 billion of cash. The net carrying value consisted primarily of $ 1.3 billion of PP&E and $ 0.1 billion of other current assets offset by $ 0.7 billion of ARO, $ 0.3 billion of deferred tax liabilities, and $ 0.2 billion of other liabilities. The before-tax earnings associated with the subsidiaries sold, including the gain on disposition noted above, were $ 851 million, $ 372 million and $ 364 million for the years ended December 31, 2020, 2019 and 2018, respectively. Production from the beginning of the year through the disposition date in May 2020 averaged 43 MBOED. Results of operations for the subsidiaries sold were reported in our Asia Pacific segment. 2019 Assets Sold In January 2019, we entered into agreements to sell our 12.4 percent ownership interests in the Golden Pass LNG Terminal and Golden Pass Pipeline. We also entered into agreements to amend our contractual obligations for retaining use of the facilities. As a result of entering into these agreements, we recorded a before-tax impairment of $ 60 million in the first quarter of 2019 which is included in the “Equity in earnings of affiliates” line on our consolidated income statement. We completed the sale in the second quarter of 2019. Results of operations for these assets were reported in our Lower 48 segment. See Note 14—Fair Value Measurement for additional information. In April 2019, we entered into an agreement to sell two ConocoPhillips U.K. subsidiaries to Chrysaor E&P Limited for $ 2.675 billion plus interest and customary adjustments, with an effective date of January 1, 2018. On September 30, 2019, we completed the sale for proceeds of $ 2.2 billion and recognized a $ 1.7 billion before-tax and $ 2.1 billion after-tax gain associated with this transaction in 2019. Together the subsidiaries sold indirectly held our exploration and production assets in the U.K. At the time of disposition, the net carrying value was approximately $ 0.5 billion, consisting primarily of $ 1.6 billion of PP&E, $ 0.5 billion of cumulative foreign currency translation adjustments, and $ 0.3 billion of deferred tax assets, offset by $ 1.8 billion of ARO and negative $ 0.1 billion of working capital. The before-tax earnings associated with the subsidiaries sold, including the gain on dispositions noted above, were $ 2.1 billion and $ 0.9 billion for the years ended December 31, 2019 and 2018, respectively. Results of operations for the U.K. were reported within our Europe, Middle East and North Africa segment. In the second quarter of 2019, we recognized an after-tax gain of $ 52 million upon the closing of the sale of our 30 percent interest in the Greater Sunrise Fields to the government of Timor-Leste for $ 350 million. The Greater Sunrise Fields were included in our Asia Pacific segment. In the fourth quarter of 2019, we sold our interests in the Magnolia field and platform for net proceeds of $ 16 million and recognized a before-tax gain of $ 82 million. At the time of sale, the net carrying value consisted of $ 4 million of PP&E offset by $ 70 million of ARO. The Magnolia results of operations were reported within our Lower 48 segment. 2018 Assets Sold In the first quarter of 2018, we completed the sale of certain properties in the Lower 48 segment for net proceeds of $ 112 million. No gain or loss was recognized on the sale. In the second quarter of 2018, we completed the sale of a package of largely undeveloped acreage in the Lower 48 segment for net proceeds of $ 105 million and no gain or loss was recognized on the sale. In the third quarter of 2018, we completed a noncash exchange of undeveloped acreage in the Lower 48 segment. The transaction was recorded at fair value resulting in the recognition of a $ 56 million gain. In the fourth quarter of 2018, we sold several packages of undeveloped acreage in the Lower 48 segment for total net proceeds of $ 162 million and recognized gains of approximately $ 140 million. On October 31, 2018, we completed the sale of our interests in the Barnett to Lime Rock Resources for $ 196 million after customary adjustments and recognized a loss of $ 5 million. We recorded an impairment of $87 million in 2018 to reduce the net carrying value of the Barnett to fair value. At the time of the disposition, our interest in Barnett had a net carrying value of $ 201 million, consisting of $ 250 million of PP&E and $ 49 million of AROs. The before-tax loss associated with our interests in the Barnett, including both the impairment and loss on disposition noted above, was $ 59 million for the year ended December 31, 2018. The Barnett results of operations were included in our Lower 48 segment. On December 18, 2018, we completed the sale of a ConocoPhillips subsidiary to BP. The subsidiary held 16.5 percent of our 24 percent interest in the BP-operated Clair Field in the U.K. We retained a 7.5 percent interest in the field. At the same time, we acquired BP’s 39.2 percent nonoperated interest in the Greater Kuparuk Area in Alaska, including their 38 percent interest in the Kuparuk Transportation Company (Kuparuk Assets). The transaction was recorded at a fair value of $ 1,743 million and was cash neutral except for customary adjustments which resulted in net proceeds of $ 253 million. At closing, our interest in the Clair Field had a net carrying value of approximately $ 1,028 million consisting primarily of $ 1,553 million of PP&E, $ 485 million of deferred tax liabilities, and $ 59 million of AROs. We recognized a before-tax gain of $ 715 million on the transaction. The 2018 before-tax earnings associated with our 16.5 percent interest in the Clair Field, including the recognized gain, were $ 748 million. Results of operations for our interest in the Clair Field are reported within our Europe, Middle East and North Africa segment and the Kuparuk Assets were included in our Alaska segment. Acquisitions In May 2018, we completed the acquisition of Anadarko’s 22 percent nonoperated interest in the Western North Slope of Alaska, as well as its interest in the Alpine Transportation Pipeline for $ 386 million, after customary adjustments. This transaction was accounted for as a business combination resulting in the recognition of approximately $ 297 million of proved property and $ 114 million of unproved property within PP&E, $ 20 million of inventory, $ 14 million of investments, and $ 59 million of AROs. These assets are included in our Alaska segment. As discussed in the Clair Field transaction with BP above, we acquired BP’s Kuparuk Assets on December 18, 2018. The transaction was accounted for as an asset acquisition with a net acquisition cost of $ 1,490 million, comprised of the fair value of $ 1,743 million associated with the disposed 16.5 percent of our 24 percent interest in the Clair Field, reduced by the net proceeds of $ 253 million. Accordingly, we recorded approximately $ 1.9 billion to proved property within PP&E, $ 42 million to inventory, $ 15 million to investments, $ 374 million of AROs, and a $ 100 million decrease to net working capital. The Kuparuk Assets are included in our Alaska segment.