Description of Business, Organization, and Liquidity	9 Months Ended
Description of Business, Organization, and Liquidity	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business, Organization, and Liquidity	Description of Business, Organization, and Liquidity Bicara Therapeutics Inc. (“Bicara” or the “Company”) was incorporated in the state of Delaware in December 2018 and is a clinical-stage biopharmaceutical company based in Boston, Massachusetts. The Company is committed to bringing transformative bifunctional therapies to patients with solid tumors. Its lead program ficerafusp alfa is a bifunctional antibody that combines a clinically validated epidermal growth factor receptor directed monoclonal antibody with a domain that binds to human transforming growth factor beta. Since inception, the Company has operated in the preclinical and clinical stages and has devoted substantially all its time and efforts to performing research and development activities, raising capital, and recruiting management and technical staff to support these operations. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, risks associated with the successful research, development and manufacturing of product candidates, competition from other companies, dependence on key personnel, protection of intellectual property, compliance with government regulations and the ability to secure additional capital to fund operations. Current and future programs will require significant research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel, and infrastructure. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, Bicara will realize significant revenue from product sales. Reverse Stock Split In September 2024, the Company’s board of directors approved an amendment to the fourth amended and restated certificate of incorporation to effect a reverse split of shares of the Company’s common stock and redeemable convertible preferred stock on a 9.2435-to-1 basis (the “Reverse Stock Split”) which was effected on September 5, 2024. The par value and authorized number of shares of common stock and redeemable convertible preferred stock were not adjusted as a result of the Reverse Stock Split. All share data and per share data amounts for all periods presented in the condensed consolidated financial statements and notes thereto have been retrospectively adjusted to reflect the effect of the Reverse Stock Split. Initial Public Offering ("IPO") On September 13, 2024, the Company closed its IPO, pursuant to which it issued and sold an aggregate of 17,500,000 shares of its common stock at a public offering price of $18.00 per share and the Company issued and sold 2,625,000 additional shares of its common stock to the underwriters of the IPO pursuant to the full exercise of their option to purchase additional shares, resulting in net proceeds of approximately $332.4 million, after deducting underwriting discounts, commissions and other offering expenses payable by the Company, totaling $29.8 million. Immediately prior to the closing of the IPO, the Company’s outstanding redeemable convertible preferred stock automatically converted into 33,210,876 shares of common stock. Following the closing of the IPO, no shares of redeemable convertible preferred stock were authorized or outstanding. In connection with the closing of its IPO, on September 13, 2024, the Company’s certificate of incorporation was amended and restated to authorize 500,000,000 shares of common stock, par value $0.0001 per share and 10,000,000 shares of preferred stock, par value of $0.0001 per share. The Company historically has funded its operations from the issuance of redeemable convertible preferred stock, common stock and through debt financing. The Company has incurred operating losses since inception and expects such losses and negative operating cash flows to continue for the foreseeable future. As of September 30, 2024, the Company had cash of $520.8 million and an accumulated deficit of $200.1 million. The Company expects that its cash and cash equivalents as of September 30, 2024 of $520.8 million will be sufficient to fund the operating expenditures and capital expenditure requirements necessary to advance its research efforts and clinical trials for at least one year from the date of issuance of these unaudited condensed consolidated financial statements.