Nature of Operations and Basis of Presentation	3 Months Ended
Nature of Operations and Basis of Presentation	Mar. 31, 2020
Nature of Operations and Basis of Presentation [Abstract]
Nature of Operations and Basis of Presentation	Nature of Operations and Basis of Presentation General Motors Company (sometimes referred to in this Quarterly Report on Form 10-Q as we, our, us, ourselves, the Company, General Motors or GM) designs, builds and sells trucks, crossovers, cars and automobile parts worldwide and is investing in and growing an autonomous vehicle business. We also provide automotive financing services through General Motors Financial Company, Inc. (GM Financial). We analyze the results of our operations through the following operating segments: GM North America (GMNA), GM International Operations (GMIO), GM South America (GMSA), Cruise, and GM Financial. Our GMSA and GMIO operating segments are reported as one, combined international segment, GM International (GMI). Cruise, formerly GM Cruise, is our global segment responsible for the development and commercialization of autonomous vehicle technology. Nonsegment operations are classified as Corporate. Corporate includes certain centrally recorded income and costs such as interest, income taxes, corporate expenditures and certain nonsegment-specific revenues and expenses. The accompanying condensed consolidated financial statements have been prepared in conformity with U.S. GAAP pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) for interim financial information. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The accompanying condensed consolidated financial statements include all adjustments, which consist of normal recurring adjustments and transactions or events discretely impacting the interim periods, considered necessary by management to fairly state our results of operations, financial position and cash flows. The operating results for interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in our 2019 Form 10-K. Except for per share amounts or as otherwise specified, dollar amounts presented within tables are stated in millions. Principles of Consolidation We consolidate entities that we control due to ownership of a majority voting interest and we consolidate variable interest entities (VIEs) when we are the primary beneficiary. Our share of earnings or losses of nonconsolidated affiliates is included in our consolidated operating results using the equity method of accounting when we are able to exercise significant influence over the operating and financial decisions of the affiliate. Recently Adopted Accounting Standards Effective January 1, 2020, we adopted Accounting Standards Update (ASU) 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments" (ASU 2016-13), which requires entities to use a new impairment model based on current expected credit losses (CECL) rather than incurred losses. Estimated credit losses under CECL consider relevant information about past events, current conditions and reasonable and supportable forecasts that affect the collectability of financial assets, resulting in recognition of lifetime expected credit losses at initial recognition of the related asset. We adopted ASU 2016-13 on a modified retrospective basis by recognizing an after-tax cumulative-effect adjustment to the opening balance of Retained earnings of $660 million, inclusive of $643 million related to GM Financial. The application of ASU 2016-13 increased our allowance for loan losses related to GM Financial receivables, net by $801 million and had an insignificant impact to our allowance for credit losses for Accounts and notes receivable and no adoption impact to Marketable debt securities on our condensed consolidated balance sheets. Accounting Standards Not Yet Adopted In March 2020, the Financial Accounting Standards Board issued ASU 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” (ASU 2020-04), which provides optional expedients and exceptions for applying U.S. GAAP if certain criteria are met to contracts, hedging relationships and other transactions that reference LIBOR or another reference rate expected to be discontinued. ASU 2020-04 became effective March 12, 2020 and may be applied prospectively through December 31, 2022. We do not believe the discontinuance of LIBOR will be a significant event for our Automotive arrangements. A substantial portion of GM Financial’s indebtedness bears interest at variable interest rates, primarily based on USD-LIBOR. We are currently assessing the impact the discontinuance of LIBOR or another reference rate will have on GM Financial’s contracts, hedging relationships and other transactions that, once completed, will determine the effect of adopting this guidance on our condensed consolidated financial statements.