| Commitments and Contingencies Disclosure [Text Block] | COMMITMENTS AND CONTINGENT LIABILITIES Environmental Matters Accruals for environmental matters are recorded when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated, based on current law and existing technologies. At June 30, 2017 , the Company had accrued obligations of $904 million for probable environmental remediation and restoration costs, including $152 million for the remediation of Superfund sites. These obligations are included in "Accrued and other current liabilities" and "Other noncurrent obligations" in the consolidated balance sheets. This is management’s best estimate of the costs for remediation and restoration with respect to environmental matters for which the Company has accrued liabilities, although it is reasonably possible that the ultimate cost with respect to these particular matters could range up to approximately twice that amount. Consequently, it is reasonably possible that environmental remediation and restoration costs in excess of amounts accrued could have a material impact on the Company’s results of operations, financial condition and cash flows. It is the opinion of the Company’s management, however, that the possibility is remote that costs in excess of the range disclosed will have a material impact on the Company’s results of operations, financial condition and cash flows. Inherent uncertainties exist in these estimates primarily due to unknown conditions, changing governmental regulations and legal standards regarding liability, and emerging remediation technologies for handling site remediation and restoration. At December 31, 2016 , the Company had accrued obligations of $909 million for probable environmental remediation and restoration costs, including $151 million for the remediation of Superfund sites. Environmental Matters Summary It is the opinion of the Company's management that the possibility is remote that costs in excess of those disclosed will have a material impact on the Company's results of operations, financial condition or cash flows. Litigation Asbestos-Related Matters of Union Carbide Corporation A summary of Asbestos-Related Matters of Union Carbide Corporation can be found in Note 15 to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. Introduction Union Carbide Corporation (“Union Carbide”), a wholly owned subsidiary of the Company, is and has been involved in a large number of asbestos-related suits filed primarily in state courts during the past four decades. These suits principally allege personal injury resulting from exposure to asbestos-containing products and frequently seek both actual and punitive damages. The alleged claims primarily relate to products that Union Carbide sold in the past, alleged exposure to asbestos-containing products located on Union Carbide’s premises, and Union Carbide’s responsibility for asbestos suits filed against a former Union Carbide subsidiary, Amchem Products, Inc. (“Amchem”). In many cases, plaintiffs are unable to demonstrate that they have suffered any compensable loss as a result of such exposure, or that injuries incurred in fact resulted from exposure to Union Carbide’s products. Union Carbide expects more asbestos-related suits to be filed against Union Carbide and Amchem in the future, and will aggressively defend or reasonably resolve, as appropriate, both pending and future claims. Estimating the Asbestos-Related Liability Since 2003, Union Carbide has engaged Ankura Consulting Group, LLC ("Ankura"), a third party actuarial specialist, to review Union Carbide's historical asbestos-related claim and resolution activity in order to assist Union Carbide's management in estimating the asbestos-related liability. Each year, Ankura has reviewed the claim and resolution activity to determine the appropriateness of updating the most recent Ankura study. Historically, every other year beginning in October, Ankura has completed a full review and formal update to the most recent Ankura study. Based on the December 2016 Ankura study and Union Carbide's own review of the data, and taking into account the change in accounting policy that occurred in the fourth quarter of 2016, Union Carbide's total asbestos-related liability through the terminal year of 2049, including asbestos-related defense and processing costs, was $1,490 million at December 31, 2016, and included in “Accrued and other current liabilities” and “Asbestos-related liabilities - noncurrent” in the consolidated balance sheets. Each quarter, Union Carbide reviews claims filed, settled and dismissed, as well as average settlement and resolution costs by disease category. Union Carbide also considers additional quantitative and qualitative factors such as the nature of pending claims, trial experience of Union Carbide and other asbestos defendants, current spending for defense and processing costs, significant appellate rulings and legislative developments, trends in the tort system, and their respective effects on expected future resolution costs. Union Carbide's management considers all these factors in conjunction with the most recent Ankura study and determines whether a change in the estimate is warranted. Based on Union Carbide's review of 2017 activity, it was determined that no adjustment to the accrual was required at June 30, 2017 . Union Carbide’s asbestos-related liability for pending and future claims and defense and processing costs was $1,422 million at June 30, 2017 , and approximately 14 percent of the recorded liability related to pending claims and approximately 86 percent related to future claims. Summary The Company's management believes the amounts recorded by Union Carbide for the asbestos-related liability (including defense and processing costs) reflect reasonable and probable estimates of the liability based upon current, known facts. However, future events, such as the number of new claims to be filed and/or received each year, the average cost of defending and disposing of each such claim, as well as the numerous uncertainties surrounding asbestos litigation in the United States over a significant period of time, could cause the actual costs for Union Carbide to be higher or lower than those projected or those recorded. Any such events could result in an increase or decrease in the recorded liability. Because of the uncertainties described above, Union Carbide cannot estimate the full range of the cost of resolving pending and future asbestos-related claims facing Union Carbide and Amchem. As a result, it is reasonably possible that an additional cost of disposing of Union Carbide's asbestos-related claims, including future defense and processing costs, could have a material impact on the Company's results of operations and cash flows for a particular period and on the consolidated financial position. Urethane Matters A full description of the Urethane Matters can be found in Note 15 to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. Class Action Lawsuit On February 26, 2016, the Company announced a proposed settlement of $835 million for the Urethane Matters Class Action Lawsuit, which included damages, class attorney fees and post-judgment interest. As a result, in the first quarter of 2016, the Company recorded a loss of $835 million , included in "Sundry income (expense) - net" in the consolidated statements of income and reflected in the Performance Materials & Chemicals segment. On May 11, 2016, the Company moved the $835 million settlement amount into an escrow account. On July 29, 2016, the U.S. District Court for the District of Kansas granted final approval of the settlement and the funds were released from escrow on August 30, 2016. Opt-Out Cases On April 5, 2016, the Company entered into a binding settlement for the Opt-Out Cases under which the Company would pay the named plaintiffs $400 million , inclusive of damages and attorney fees. As a result, the Company recorded a loss of $400 million in the first quarter of 2016, included in "Sundry income (expense) - net" in the consolidated statements of income and reflected in the Performance Materials & Chemicals segment. Payment of this settlement occurred on May 4, 2016. Bayer CropScience v. Dow AgroSciences ICC Arbitration On August 13, 2012, Bayer CropScience AG and Bayer CropScience NV (together, “Bayer”) filed a request for arbitration with the International Chamber of Commerce ("ICC") International Court of Arbitration against Dow AgroSciences LLC, a wholly owned subsidiary of the Company, and other subsidiaries of the Company (collectively, “DAS”) under a 1992 license agreement executed by predecessors of the parties (the “License Agreement”). In its request for arbitration, Bayer alleged that (i) DAS breached the License Agreement, (ii) the License Agreement was properly terminated with no ongoing rights to DAS, (iii) DAS has infringed and continues to infringe its patent rights related to the use of the pat gene in certain soybean and cotton seed products, and (iv) Bayer is entitled to monetary damages and injunctive relief. DAS denied that it breached the License Agreement and asserted that the License Agreement remained in effect because it was not properly terminated. DAS also asserted that all of Bayer’s patents at issue are invalid and/or not infringed, and, therefore, for these reasons (and others), a license was not required. During the pendency of the arbitration proceeding, DAS filed six re-examination petitions with the United States Patent & Trademark Office (“USPTO”) against the Bayer patents, asserting that each patent is invalid based on the doctrine against double-patenting and/or prior art. The USPTO granted all six petitions, and, on February 26, 2015, the USPTO issued an office action rejecting the patentability of the sole Bayer patent claim in the only asserted Bayer patent that has not expired and that forms the basis for the vast majority of the damages in the arbitral award discussed below. A three-member arbitration tribunal presided over the arbitration proceeding (the “tribunal”). In a decision dated October 9, 2015, the tribunal determined that (i) DAS breached the License Agreement, (ii) Bayer properly terminated the License Agreement, (iii) all of the patents remaining in the proceeding are valid and infringed, and (iv) that Bayer is entitled to monetary damages in the amount of $455 million inclusive of pre-judgment interest and costs (the “arbitral award”). One of the arbitrators, however, issued a partial dissent finding that all of the patents are invalid based on the double-patenting doctrine. The tribunal also denied Bayer’s request for injunctive relief. The arbitration award is not self-executing and must be confirmed by a court for it to be enforceable and to have the legal effect of a judgment. On October 16, 2015, Bayer filed a motion in U.S. District Court for the Eastern District of Virginia ("Federal District Court") seeking to confirm the arbitral award. DAS opposed the motion and filed separate motions to vacate the award, or in the alternative, to stay enforcement of the award until the USPTO issues final office actions with respect to the re-examination proceedings. On January 15, 2016, the Federal District Court denied DAS's motions and confirmed the award. DAS appealed the Federal District Court's decision and posted a bond to stay enforcement of the award during the appeal. On March 1, 2017, the U.S. Court of Appeals for the Federal Circuit ("Federal Circuit") affirmed the arbitral award. As a result of this action, in the first quarter of 2017, the Company recorded a loss of $469 million , inclusive of the arbitral award and post-judgment interest, which is included in "Sundry income (expense) - net" in the consolidated statements of income and reflected in the Agricultural Sciences segment. On March 31, 2017, DAS filed a combined petition for Rehearing or Rehearing En Banc with the Federal Circuit which was denied on May 12, 2017. On May 19, 2017, the Federal Circuit issued a mandate denying DAS's request to stay the arbitral award pending judicial review by the United States Supreme Court. On May 26, 2017, the Company paid the $469 million arbitral award to Bayer. The Company continues to believe the arbitral award is fundamentally flawed in numerous respects because it (i) violates U.S. public policy prohibiting enforcement of invalid patents, (ii) manifestly disregards applicable law, and (iii) disregards unambiguous contract provisions and ignores the essence of the applicable contracts. The USPTO has now issued office actions rejecting the patentability of all four patents that Bayer asserted in the case. The Company is continuing to pursue its legal rights with respect to this matter, including by filing a petition for writ of certiorari with the United States Supreme Court. The arbitral award will not impact DAS’s commercialization of its soybean and cotton seed products, including those containing the ENLIST™ technologies. Rocky Flats Matter A summary of the Rocky Flats Matter can be found in Note 15 to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. The Company and Rockwell International Corporation ("Rockwell") (collectively, the "defendants") were defendants in a class action lawsuit filed in 1990 on behalf of property owners ("plaintiffs") in Rocky Flats, Colorado, who asserted claims for nuisance and trespass based on alleged property damage caused by plutonium releases from a nuclear weapons facility owned by the U.S. Department of Energy ("DOE") (the "facility") but operated by Dow and Rockwell. The plaintiffs tried their case as a public liability action under the Price Anderson Act ("PAA"). Dow and Rockwell litigated this matter in the U.S. District Court for the District of Colorado ("District Court"), the U.S. Tenth Circuit Court of Appeals and then filed a petition for writ of certiorari in the United States Supreme Court. On May 18, 2016, Dow, Rockwell and the plaintiffs entered into a settlement agreement for $375 million , of which $131 million was paid by Dow. The DOE authorized the settlement pursuant to the PAA and the nuclear hazards indemnity provisions contained in Dow's and Rockwell's contracts. The District Court granted preliminary approval to the class settlement on August 5, 2016. On April 28, 2017, the District Court conducted a fairness hearing and granted final judgment approving the class settlement and dismissed class claims against the defendants ("final judgment order"). The litigation is now concluded. On December 13, 2016, the United States Civil Board of Contract Appeals unanimously ordered the United States government to pay the amounts stipulated in the settlement agreement. On January 17, 2017, the Company received a full indemnity payment of $131 million from the United States government for Dow's share of the class settlement. On January 26, 2017, the Company placed $130 million in an escrow account for the settlement payment owed to the plaintiffs. The funds were subsequently released from escrow as a result of the final judgment order. At June 30, 2017 , there are no outstanding balances in the consolidated balance sheets related to this matter ( $131 million included in "Accounts and notes receivable - Other" and $130 million included in "Accrued and other current liabilities" at December 31, 2016 ). Dow Corning Chapter 11 Related Matters A summary of the Dow Corning Chapter 11 Related Matters can be found in Note 15 to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. Introduction In 1995, Dow Corning, then a 50:50 joint venture between Dow and Corning voluntarily filed for protection under Chapter 11 of the U.S. Bankruptcy Code in order to resolve Dow Corning’s breast implant liabilities and related matters (the “Chapter 11 Proceeding”). Dow Corning emerged from the Chapter 11 Proceeding on June 1, 2004 (the “Effective Date”) and is implementing the Joint Plan of Reorganization (the “Plan”). The Plan provides funding for the resolution of breast implant and other product liability litigation covered by the Chapter 11 Proceeding and provides a process for the satisfaction of commercial creditor claims in the Chapter 11 Proceeding. As of June 1, 2016, Dow Corning is a wholly owned subsidiary of Dow. Breast Implant and Other Product Liability Claims Under the Plan, a product liability settlement program administered by an independent claims office (the “Settlement Facility”) was created to resolve breast implant and other product liability claims. Product liability claimants rejecting the settlement program in favor of pursuing litigation must bring suit against a litigation facility (the “Litigation Facility”). Under the Plan, total payments committed by Dow Corning to resolving product liability claims are capped at a maximum $2,350 million net present value (“NPV”) determined as of the Effective Date using a discount rate of seven percent (approximately $3,685 million undiscounted at June 30, 2017 ). Of this amount, no more than $400 million NPV determined as of the Effective Date can be used to fund the Litigation Facility. Dow Corning has an obligation to fund the Settlement Facility and the Litigation Facility over a 16-year period, commencing at the Effective Date. As of June 30, 2017 , Dow Corning and its insurers have made life-to-date payments of $1,762 million to the Settlement Facility and the Settlement Facility reported an unexpended balance of $140 million . Dow Corning's liability for breast implant and other product liability claims ("Implant Liability") was $263 million at June 30, 2017 ( $263 million at December 31, 2016), which is included in "Other noncurrent obligations" in the consolidated balance sheets. Dow Corning is not aware of circumstances that would change the factors used in estimating the Implant Liability and believes the recorded liability reflects the best estimate of the remaining funding obligations under the Plan; however, the estimate relies upon a number of significant assumptions, including: future claim filing levels in the Settlement Facility will be similar to those in the revised settlement program, which management uses to estimate future claim filing levels for the Settlement Facility; future acceptance rates, disease mix, and payment values will be materially consistent with historical experience; no material negative outcomes in future controversies or disputes over Plan interpretation will occur; and the Plan will not be modified. If actual outcomes related to any of these assumptions prove to be materially different, the future liability to fund the Plan may be materially different than the amount estimated. If Dow Corning was ultimately required to fund the full liability up to the maximum capped value, the liability would be $1,923 million at June 30, 2017 . Commercial Creditor Issues The Plan provides that each of Dow Corning’s commercial creditors (the “Commercial Creditors”) would receive in cash the sum of (a) an amount equal to the principal amount of their claims and (b) interest on such claims. The actual amount of interest that will ultimately be paid to these Commercial Creditors is uncertain due to pending litigation between Dow Corning and the Commercial Creditors regarding the appropriate interest rates to be applied to outstanding obligations from the 1995 bankruptcy filing date through the Effective Date, as well as the presence of any recoverable fees, costs and expenses. Upon the Plan becoming effective, Dow Corning paid approximately $1,500 million to the Commercial Creditors, representing principal and an amount of interest that Dow Corning considers undisputed. In 2006, the U.S. Court of Appeals for the Sixth Circuit concluded that there is a general presumption that contractually specified default interest should be paid by a solvent debtor to unsecured creditors (the “Interest Rate Presumption”) and permitting Dow Corning’s Commercial Creditors to recover fees, costs, and expenses where allowed by the relevant loan agreements. The matter was remanded to the U.S. District Court for the Eastern District of Michigan ("District Court") for further proceedings, including rulings on the facts surrounding specific claims and consideration of any equitable factors that would preclude the application of the Interest Rate Presumption. On May 10, 2017, the District Court entered a stipulated order resolving pending discovery motions and established a discovery schedule for the Commercial Creditors matter. As a result, Dow Corning and its third party consultants conducted further analysis of the Commercial Creditors claims and defenses. This analysis indicated the estimated remaining liability to Commercial Creditors to be within a range of $77 million to $260 million . No single amount within the range appears to be a better estimate than any other amount within the range. Therefore, Dow Corning recorded the minimum liability within the range, which resulted in a decrease to the Commercial Creditor liability of $33 million , which was included in "Sundry income (expense) - net" in the consolidated statements of income. At June 30, 2017 , the liability related to Dow Corning’s potential obligation to pay additional interest to its Commercial Creditors in the Chapter 11 Proceeding was $77 million and is included in "Accrued and other current liabilities" in the consolidated balance sheets ( $108 million at December 31, 2016). The actual amount of interest that will be paid to these creditors is uncertain and will ultimately be resolved through continued proceedings in the District Court. Indemnifications In connection with the June 1, 2016 ownership restructure of Dow Corning, the Company is indemnified by Corning for 50 percent of future losses associated with certain pre-closing liabilities, including the Implant Liability and Commercial Creditors matters described above, subject to certain conditions and limits. The maximum amount of indemnified losses which may be recovered are subject to a cap that declines over time. Indemnified losses are capped at (1) $1.5 billion until May 31, 2018, (2) $1 billion between May 31, 2018 and May 31, 2023, and (3) no recoveries are permitted after May 31, 2023. No indemnification assets were recorded at June 30, 2017 or December 31, 2016 . Summary The amounts recorded by Dow Corning for the Chapter 11 related matters described above were based on current, known facts, which management believes reflect reasonable and probable estimates of the liability. However, future events could cause the actual costs for Dow Corning to be higher or lower than those projected or those recorded. Any such events could result in an increase or decrease in the recorded liability. Other Litigation Matters In addition to the specific matters described above, the Company is party to a number of other claims and lawsuits arising out of the normal course of business with respect to product liability, patent infringement, employment matters, governmental tax and regulation disputes, contract and commercial litigation, and other actions. Certain of these actions purport to be class actions and seek damages in very large amounts. All such claims are being contested. Dow has an active risk management program consisting of numerous insurance policies secured from many carriers at various times. These policies may provide coverage that could be utilized to minimize the financial impact, if any, of certain contingencies described above. It is the opinion of the Company’s management that the possibility is remote that the aggregate of all such other claims and lawsuits will have a material adverse impact on the results of operations, financial condition and cash flows of the Company. Gain Contingency - Dow v. Nova Chemicals Corporation Patent Infringement Matter On December 9, 2010, Dow filed suit in the Federal Court in Ontario, Canada ("Federal Court") alleging that Nova Chemicals Corporation ("Nova") was infringing the Company's Canadian polyethylene patent 2,106,705 (the "'705 Patent"). Nova counterclaimed on the grounds of invalidity and non-infringement. In accordance with Canadian practice, the suit was bifurcated into a merits phase, followed by a damages phase. Following trial in the merits phase, in May 2014 the Federal Court ruled that the Company's '705 Patent was valid and infringed by Nova. Nova appealed to the Canadian Federal Court of Appeal, which affirmed the Federal Court decision in August 2016. Nova then sought leave to appeal its loss to the Supreme Court of Canada, which dismissed Nova’s petition in April 2017. As a result, Nova has exhausted all appeal rights on the merits, and it is undisputed that Nova owes Dow the profits it earned from its infringing sales as determined in the trial for the damages phase. On April 19, 2017, the Federal Court issued a Public Judgment in the damages phase, which detailed its conclusions on how to calculate the profits to be awarded to Dow. Dow and Nova submitted their respective calculations of the damages to the Federal Court in May 2017. On June 29, 2017, the Federal Court issued a Confidential Supplemental Judgment, concluding that Nova must pay $645 million Canadian dollars (equivalent to $495 million U.S. dollars) to Dow, plus pre- and post-judgment interest, for which Dow received payment of $501 million from Nova on July 6, 2017. Although Nova is appealing portions of the damages judgment, certain portions of it are indisputable and will be owed to Dow regardless of the outcome of any further appeals by Nova. As a result of these actions and in accordance with ASC 450-30 "Gain Contingencies," the Company recorded a $160 million pretax gain in the second quarter of 2017, reflected in the Performance Plastics segment, of which $137 million is included in "Sundry income (expense) - net" and $23 million is included in "Selling, general and administrative expenses" in the consolidated statements of income. At June 30, 2017 , included in the Company's consolidated balance sheets was $501 million in "Accounts and notes receivable - Other" for the damages judgment and $341 million in "Other noncurrent obligations" related to the disputed portion of the damages judgment. Dow is confident of its chances of defending the entire judgment on appeal, particularly the trial court's determinations on important factual issues, which will be accorded deferential review on appeal. Purchase Commitments A summary of the Company's purchase commitments can be found in Note 15 to the Consolidated Financial Statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. There have been no material changes to the purchase commitments since December 31, 2016 . Guarantees The following table provides a summary of the final expiration, maximum future payments and recorded liability reflected in the consolidated balance sheets for each type of guarantee: Guarantees At June 30, 2017 At December 31, 2016 In millions Final Expiration Maximum Future Payments Recorded Liability Final Expiration Maximum Future Payments Recorded Liability Guarantees 2021 $ 4,886 $ 73 2021 $ 5,096 $ 86 Residual value guarantees 2027 998 134 2027 947 134 Total guarantees $ 5,884 $ 207 $ 6,043 $ 220 Guarantees Guarantees arise during the ordinary course of business from relationships with customers and nonconsolidated affiliates when the Company undertakes an obligation to guarantee the performance of others (via delivery of cash or other assets) if specified triggering events occur. With guarantees, such as commercial or financial contracts, non-performance by the guaranteed party triggers the obligation of the Company to make payments to the beneficiary of the guarantee. The majority of the Company’s guarantees relate to debt of nonconsolidated affiliates, which have expiration dates ranging from less than one year to four years, and trade financing transactions in Latin America, which typically expire within one year of inception. The Company’s current expectation is that future payment or performance related to the non-performance of others is considered unlikely. The Company has entered into guarantee agreements (“Guarantees”) related to project financing for Sadara Chemical Company ("Sadara"), a nonconsolidated affiliate. The total of an Islamic bond and additional project financing (collectively “Total Project Financing”) obtained by Sadara is approximately $12.5 billion . Sadara had $12.4 billion of Total Project Financing outstanding at June 30, 2017 ( $12.4 billion at December 31, 2016 ). The Company's guarantee of the Total Project Financing is in proportion to the Company's 35 percent ownership interest in Sadara, or up to approximately $4.4 billion when the project financing is fully drawn. The Guarantees will be released upon completion of construction of the Sadara complex and satisfactory fulfillment of certain other conditions, including passage of an extensive operational testing program, which is currently anticipated by the end of 2018 and must occur no later than December 2020. Residual Value Guarantees The Company provides guarantees related to leased assets specifying the residual value that will be available to the lessor at lease termination through sale of the assets to the lessee or third parties. Asset Retirement Obligations The Company has recognized asset retirement obligations for the following activities: demolition and remediation activities at manufacturing and administrative sites primarily in the United States, Canada, Argentina, Brazil, Colombia and Europe; and capping activities at landfill sites in the United States, Canada, Brazil and Italy. The Company has also recognized conditional asset retirement obligations related to asbestos encapsulation as a result of planned demolition and remediation activities at manufacturing and administrative sites primarily in the United States, Canada, Argentina, Brazil, Colombia and Europe. The aggregate carrying amount of asset retirement obligations recognized by the Company was $109 million at June 30, 2017 ( $110 million at December 31, 2016 ). These obligations are included in the consolidated balance sheets as "Accrued and other current liabilities" and "Other noncurrent obligations." The Company has not recognized conditional asset retirement obligations for which a fair value cannot be reasonably estimated in its consolidated financial statements. It is the opinion of the Company’s management that the possibility is remote that such conditional asset retirement obligations, when estimable, will have a material impact on the Company’s consolidated financial statements based on current costs. |
