Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Other program candidates Other Program Candidates [Member] Other Program Candidates Maximum Maximum [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] 2021 Equity Incentive Plan Two Thousand and Twenty One Equity Incentive Plan [Member] 2021 Equity incentive plan. Income Tax Jurisdiction, Domestic Federal Income Tax Jurisdiction, Domestic Federal [Member] Title of 12(b) Security Title of 12(b) Security Debt Securities, Available-for-Sale [Table] Debt Securities, Available-for-Sale [Table] Document Fiscal Year Focus Document Fiscal Year Focus Adjustment to Compensation, Amount Adjustment to Compensation Amount Financial Instrument [Axis] Financial Instrument [Axis] Segment Reporting [Abstract] Common stock, $0.0001 par value per share; 200,000,000 shares authorized as of June 30, 2026 and December 31, 2025; and 5,306,894 and 5,283,321 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively Common Stock, Value, Issued Other prepaids Other Prepaid Expense, Current Entity Ex Transition Period Entity Ex Transition Period Restatement Determination Date Restatement Determination Date Investment in joint venture Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Measurement Frequency [Axis] Measurement Frequency [Axis] Number of securities called by warrants or rights (in shares) Class of Warrant or Right, Number of Securities Called by Warrants or Rights Schedule of Prepaid Expenses and Other Current Assets Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block] Amendment Flag Amendment Flag Scientific and finance accounting support Scientific And Finance And Accounting Related Support Scientific And Finance And Accounting Related Support Proceeds from sale of equity method investments Proceeds from Sale of Equity Method Investments Current liabilities: Liabilities, Current [Abstract] Entity Common Stock, Shares Outstanding (in shares) Entity Common Stock, Shares Outstanding Gross Unrealized Holding Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Milestone payment received Proceeds From Sale Of Equity Method Investments, Milestone Payment Received Proceeds From Sale Of Equity Method Investments, Milestone Payment Received Schedule of Fair Value of Marketable Securities by Type of Security Debt Securities, Available-for-Sale [Table Text Block] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Nonvested restricted stock awards/units, at the beginning of the period (in shares) Nonvested restricted stock awards/units, at the end of the period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Weighted-average common shares outstanding, basic (in shares) Weighted-average number of common shares outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current Interest income Interest and Other Income Effective income tax rate reconciliation, percent Effective Income Tax Rate Reconciliation, Adjusted, Percent Effective Income Tax Rate Reconciliation, Adjusted, Percent Entity Address, City or Town Entity Address, City or Town Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Level 2 Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] 2021 Employee Stock Purchase Plan Two Thousand Twenty One Employee Stock Purchase Plan [Member] 2021 Employee stock purchase plan. Other comprehensive loss Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Termination fee Business Combination, Termination Fee Business Combination, Termination Fee Percent excess limit (as a percent) Exceed Limit Percentage With Exercise To Aggregate Shares Of Common Stock Beneficially Owned Exceed limit percentage with exercise to aggregate shares of common stock beneficially owned. License License [Member] Recently Issued Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Deferred revenue Increase (Decrease) in Contract with Customer, Liability Schedule of Segment Reporting Segment Reporting [Table Text Block] Schedule of Accrued Expenses Schedule of Accrued Liabilities [Table Text Block] Pre-funded warrants exercise price (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Document Period End Date Document Period End Date Changes in operating assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Net cash provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding STOCKHOLDERS' EQUITY Equity [Text Block] Security Exchange Name Security Exchange Name Granted (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Tax Credit Carryforward [Table] Tax Credit Carryforward [Table] Purchases of marketable securities Payments to Acquire Marketable Securities Accumulated other comprehensive gain Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Operating lease liabilities Operating Lease, Liability, Current NET INCOME (LOSS) PER COMMON SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings Per Share [Abstract] Earnings Per Share [Abstract] Proceeds from maturities of marketable securities Proceeds from Sale and Maturity of Marketable Securities Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Total liabilities Liabilities Trading Symbol Trading Symbol Termination charges Termination Charges Termination charges. Entity Bankruptcy Proceedings, Reporting Current Entity Bankruptcy Proceedings, Reporting Current Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Candid Merger Candid [Member] Candid Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Unrecognized share-based compensation expense Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Income tax liabilities Accrued Income Taxes, Current Company Selected Measure Name Company Selected Measure Name Sale of Stock [Domain] Sale of Stock [Domain] Effect of potentially dilutive securities: Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Concurred financing Merger And Reorganization, Concurrent Financing Merger And Reorganization, Concurrent Financing Asset Class [Domain] Asset Class [Domain] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Cash Flows Provided by (Used in) Operating Activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Weighted-average common shares outstanding, diluted (in shares) Weighted-average number of common shares outstanding, diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Additional financial support outside of capital contribution Additional Financial Support Outside Of Capital Contribution Additional Financial Support Outside Of Capital Contribution Days of notice Period Of Notice Days Affects Exceed Limit Percentage With Exercise To Aggregate Shares Of Common Stock Beneficially Owned Period Of Notice Days Affects Exceed Limit Percentage With Exercise To Aggregate Shares Of Common Stock Beneficially Owned Underlying Security Market Price Change Underlying Security Market Price Change, Percent U.S. treasury securities US Treasury Securities [Member] Operating loss carryforwards Operating Loss Carryforwards Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Common stock shares outstanding (in shares) Share Based Compensation Arrangement By Share Based Payment Award Annual Increase In Number Of Shares Minimum Share Based Compensation Arrangement By Share Based Payment Award Annual Increase In Number Of Shares Minimum Award Timing Predetermined Award Timing Predetermined [Flag] Debt Securities, Available-for-Sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Severance costs Severance incurred during the period Severance Costs Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Share-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Level 1 Fair Value, Inputs, Level 1 [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Issuance of common stock under the stock award plan (in shares) Stock Issued During Period Shares Vested Stock issued during period shares vested. Effect of potentially dilutive securities (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Nonvested restricted stock awards/units, beginning balance (in dollars per share) Nonvested restricted stock awards/units, ending balance (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Schedule of Marketable Securities by Balance Sheet Location Classification Available For Sale Securities By Balance Sheet Location Classification [Table Text Block] Available for sale securities by balance sheet location classification. Rallybio Rallybio [Member] Rallybio All Executive Categories All Executive Categories [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Plan Name [Domain] Plan Name [Domain] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Outstanding stock options at beginning of period (in dollars per share) Outstanding stock options at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Schedule of Basic and Diluted Net Loss Per Common Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Risk free interest rate, maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum SEGMENTS Segment Reporting [Text Block] MARKETABLE SECURITIES Investment in Debt and Equity Securities and Other Trading Assets [Text Block] Minimum Minimum [Member] Expiration Date Trading Arrangement Expiration Date Equity method investment, net consideration Equity Method Investment, Net Consideration Equity Method Investment, Net Consideration Income Statement Location [Axis] Location, Statement of Income, Balance [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Outstanding stock options, weighted-average contractual term (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted-Average Remaining Contractual Term Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Research and development Prepaid Research and Development Expenses Prepaid research and development expenses. Exercise price (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Exercise Price Measurement Input, Premium Measurement Input, Premium [Member] Measurement Input, Premium Exercisable stock options at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Collaboration agreement term Collaboration Agreement, Term Collaboration Agreement, Term Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Sale of common stock, number of shares issued in transaction (in shares) Sale of Stock, Number of Shares Issued in Transaction Collaboration and license revenue Collaboration And License Revenue [Member] Collaboration And License Revenue Sale of common stock, premium on stock price (as a percent) Sale Of Stock, Premium On Stock Price, Percentage Sale Of Stock, Premium On Stock Price, Percentage Compensation and related expenses Accrued Employee Benefits, Current Exercise Price Award Exercise Price Schedule of Restructuring and Related Costs [Table] Restructuring Cost [Table] Cash Flows Provided by Investing Activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Segment Reporting [Line Items] Segment Reporting [Line Items] Document Quarterly Report Document Quarterly Report Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Segments [Domain] Segments [Domain] Schedule of License and Collaboration Agreements [Line Items] Schedule of License and Collaboration Agreements [Line Items] Schedule of License and Collaboration Agreements Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Income (loss) before equity in losses of joint venture Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Percentage of common stock beneficially owned not exceed (as a percent) Percentage of Common Stock Beneficially Owned Not Exceed Percentage of common stock beneficially owned not exceed. Schedule of Restructuring and Related Costs Restructuring and Related Costs [Table Text Block] Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Equity method investments Equity Method Investments Beginning balance Ending balance Restructuring Reserve Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Measurement Input Type [Domain] Measurement Input Type [Domain] Gross proceeds Sale of Stock, Consideration Received on Transaction Adoption Date Trading Arrangement Adoption Date Counterparty Name [Domain] Counterparty Name [Domain] Total stockholders' equity Beginning balance Ending balance Equity, Attributable to Parent Total other income, net Nonoperating Income (Expense) Insurance Prepaid Insurance Assets Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Risk free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Fair Value, Nonrecurring Fair Value, Nonrecurring [Member] Insider Trading Policies and Procedures [Line Items] Outstanding stock options at beginning of period (in shares) Outstanding stock options at end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Prepaid expenses and other current assets Prepaid expenses and other assets Prepaid Expense and Other Assets, Current BALANCE SHEET COMPONENTS Supplemental Balance Sheet Disclosures [Text Block] Business Combination [Domain] Business Combination [Domain] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Number of operating segments Number of Operating Segments Antidilutive securities excluded from computation of earnings per share, amount (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Entity Central Index Key Entity Central Index Key All Adjustments to Compensation All Adjustments to Compensation [Member] Securities Purchase Agreement Securities Purchase Agreement [Member] Securities Purchase Agreement Business Combination [Axis] Business Combination [Axis] Equity [Abstract] Equity [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Restructuring costs incurred Restructuring and Related Cost, Incurred Cost Income Taxes Income Tax, Policy [Policy Text Block] Net cash provided by (used in) operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation RE Ventures I, LLC RE Ventures I, LLC [Member] RE Ventures I, LLC. Income Statement [Abstract] Income Statement [Abstract] Issuance of common stock under the stock purchase plan (in shares) Shares issued during period (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Document Transition Report Document Transition Report Ownership [Axis] Ownership [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Investment, Name [Axis] Investment, Name [Axis] Operating expenses: Operating Expenses [Abstract] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Schedule of Assumptions of Fair Value of Stock Option Pricing Granted Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Number of Option Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] City Area Code City Area Code ACCUMULATED OTHER COMPREHENSIVE GAIN (LOSS) AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Measurement Input, Price Volatility Measurement Input, Price Volatility [Member] Name Forgone Recovery, Individual Name Total unrecognized share-based compensation expense, weighted average period for recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Balance Sheet Related Disclosures [Abstract] Balance Sheet Related Disclosures [Abstract] Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Weighted-Average Grant Date Fair Value Per Share Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Statement [Line Items] Statement [Line Items] Total assets Assets Entity [Domain] Entity [Domain] Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Common stock issuable (in shares) Common Stock, Capital Shares Reserved for Future Issuance JJDC Johnson & Johnson Innovation - JJDC, Inc. [Member] Johnson & Johnson Innovation - JJDC, Inc. Weighted average grant date fair value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Proceeds from the issuance of common stock under the stock purchase plan Proceeds, Issuance of Shares, Share-Based Payment Arrangement, Excluding Option Exercised Gross Unrealized Holding Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Issuance of common stock under the stock purchase plan Stock Issued During Period, Value, Employee Stock Purchase Plan BUSINESS AND LIQUIDITY Nature of Operations [Text Block] PEO PEO [Member] Beginning balance (in shares) Ending balance (in shares) Shares, Outstanding Reporting Segment Reporting Segment [Member] Reporting Segment Expired (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Future equity method investment, milestone, cash payment Future Equity Method Investment, Milestone, Cash Payment Future Equity Method Investment, Milestone, Cash Payment Total share-based compensation Share-Based Payment Arrangement, Expense Marketable securities Marketable Securities, Current Additional shares authorized (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Issuance of common stock from exercise of stock options (in shares) Exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One ACCUMULATED DEFICIT Retained Earnings [Member] Operating lease liabilities, noncurrent Operating Lease, Liability, Noncurrent Total operating expenses Operating Expenses Forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Net income per common share, diluted (in dollars per share) Net income per common share, diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Expected volatility, maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Total Shareholder Return Amount Total Shareholder Return Amount Prepaid expenses, operating lease right-of-use assets and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Ownership [Domain] Ownership [Domain] Research and development Research and development: Research and Development Expense Severance paid and adjustments made during the period Payments for Severance Payments for Severance Adjustments to reconcile net loss to net cash provided by (used in) operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Cash Flows Provided by Financing Activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Property and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Offering price (in dollars per share) Shares Issued, Price Per Share Investment in joint venture Investment in joint venture Payments to Acquire Interest in Joint Venture Financial Instruments [Domain] Financial Instruments [Domain] Other comprehensive gain (loss): Other Comprehensive Income (Loss), Tax [Abstract] Allowance for credit losses Financing Receivable, Allowance for Credit Loss Issuance of common stock from exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Stock Options and Nonvested Restricted Share Stock Options And Unvested Restricted Share [Member] Stock options and unvested restricted share. Forfeited (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price RLYB212 RLYB212 [Member] RLYB212 Income Tax Jurisdiction, Domestic State and Local Income Tax Jurisdiction, Domestic State and Local [Member] Tax Credit Carryforward [Line Items] Tax Credit Carryforward [Line Items] Risk free interest rate, minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Segment Reporting [Table] Segment Reporting [Table] Shares available for future issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Schedule of Equity Method Investments [Table] Equity Method Investment [Table] Sale of Stock [Axis] Sale of Stock [Axis] Weighted-Average Contractual Term (in years) and Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract] Other current assets Other Assets, Current Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Other income: Other Nonoperating Income (Expense) [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Loss from operations Operating Income (Loss) Current Fiscal Year End Date Current Fiscal Year End Date Interest of joint venture entity (as a percent) Percentage Of Interest Of Joint Venture Entity Percentage of interest of the joint venture entity Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Restructuring Reserve [Roll Forward] Restructuring Reserve [Roll Forward] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Schedule of Fair Values of Available-for-Sale Debt Securities by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of Stock Option Activity Share-Based Payment Arrangement, Option, Activity [Table Text Block] Weighted-Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Units Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Common stock, shares issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] INVESTMENT IN JOINT VENTURE Equity Method Investments and Joint Ventures Disclosure [Text Block] Net accretion of discounts/premiums on debt securities Amortization of Debt Discount (Premium) Reimbursement of transaction costs Reimbursement Of Transaction Costs Reimbursement Of Transaction Costs Continuous unrealized loss position for more than twelve months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Equity Components [Axis] Equity Components [Axis] Product and Service [Domain] Product and Service [Domain] Class of Stock [Line Items] Class of Stock [Line Items] Entity Interactive Data Current Entity Interactive Data Current Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Discount rate used to estimated future contingent milestone and royalties Discount Rate Used To Estimated Future Contingent Milestone And Royalties Discount Rate Used To Estimated Future Contingent Milestone And Royalties Entity Small Business Entity Small Business Comprehensive gain (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Marketable securities Marketable Securities [Member] Marketable securities. Termination Date Trading Arrangement Termination Date Merger valuation amount Merger And Reorganization, Consideration Transferred, Expected Value Merger And Reorganization, Consideration Transferred, Expected Value Other expenses Other Expenses [Member] Other Expenses Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Other assets, noncurrent Other Assets, Noncurrent Document Type Document Type Accrued expenses Accrued expenses Accrued Liabilities, Current Fair Value as of Grant Date Award Grant Date Fair Value Business tax credit carryforward, amount Tax Credit Carryforward, Amount Loss on disposal of assets Gain (Loss) on Disposition of Assets Exercisable stock options, aggregate intrinsic value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Other assets, miscellaneous, current Other Assets, Miscellaneous, Current Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Cash and cash equivalents Cash and cash equivalents Cash and Cash Equivalents [Member] Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Commitments and contingencies (Note 7) Commitments and Contingencies Total revenue Revenue Revenues Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Gain on sale of joint venture Equity Method Investment, Realized Gain (Loss) on Disposal Loss on investment in joint venture Loss on investment in joint venture Allocable share of losses recorded Income (Loss) from Equity Method Investments Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Schedule of Nonvested Restricted Common Stock Units Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Total available-for-sale debt securities by contractual maturity Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value Counterparty Name [Axis] Counterparty Name [Axis] Expired (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Expirations in Period Liabilities and stockholders' equity Liabilities and Equity [Abstract] Exercisable stock options, weighted-average contractual term (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term General and administrative, personnel expenses (including share-based compensation) General and Administrative Expense, Personnel Expenses General and Administrative Expense, Personnel Expenses Award Type [Domain] Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount U.S. government agency securities US Government Agencies Debt Securities [Member] Research and development Accrued Research And Development Expenses Current Accrued research and development expenses current. Expected term (years) Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Share price (per share) Share Price PEO Name PEO Name Accrued expenses, tax liability and operating lease liabilities Increase (Decrease) in Accrued Liabilities Merger and reorganization, combined ownership percentage Merger And Reorganization, Combined Ownership Percentage Merger And Reorganization, Combined Ownership Percentage Upfront payment Contract with Customer, Liability Cash, cash equivalents and marketable securities Cash, Cash Equivalents, and Short-Term Investments Other segment items Segment Reporting, Other Segment Item, Amount Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Pre-Funded Warrants Pre-Funded Warrant [Member] Pre-funded warrant. Legal Entity [Axis] Legal Entity [Axis] Exercised (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Cash and cash equivalents — beginning of period Cash and cash equivalents — end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation General and administrative, excluding personnel expenses General and Administrative Expense, Excluding Personnel Expenses General and Administrative Expense, Excluding Personnel Expenses Professional fees Accrued Professional Fees, Current Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] Accounts payable Increase (Decrease) in Accounts Payable Other accrued expenses Other Accrued Liabilities, Current Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Measurement Frequency [Domain] Measurement Frequency [Domain] Future contingent milestone and royalty assets Future Contingent Milestone and Royalty Assets Future Contingent Milestone and Royalty Assets Share-based compensation Share-Based Payment Arrangement, Noncash Expense Share-based compensation arrangement by share-based payment award, purchase price of common stock (as a percent) Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent Investment, Name [Domain] Investment, Name [Domain] Net income (loss) per common share, basic (in dollars per share) Net income (loss) per common share, basic (in dollars per share) Earnings Per Share, Basic Measurement Input Type [Axis] Measurement Input Type [Axis] Deferred revenue Contract with Customer, Liability, Current Measurement Input, Risk Free Interest Rate Measurement Input, Risk Free Interest Rate [Member] Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Award Type [Axis] Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accumulated deficit Retained Earnings (Accumulated Deficit) Future contingent milestone and royalty assets, current Future Contingent Milestone And Royalty Assets, Current Future Contingent Milestone And Royalty Assets, Current Restructuring and Related Activities [Abstract] Product and Service [Axis] Product and Service [Axis] Allocated amounts Equity Securities, FV-NI Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] COMMON Common Stock [Member] Fair Value Debt securities, available-for-sale Debt Securities, Available-for-Sale Expected volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Positions eliminated (as a percent) Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Expected dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Pre-Merger Equityholders of Rallybio Pre-Merger Equityholders of Rallybio [Member] Pre-Merger Equityholders of Rallybio Equity Awards Adjustments Equity Awards Adjustments [Member] COLLABORATION AND LICENSE AGREEMENTS Collaborative Arrangement Disclosure [Text Block] Total liabilities and stockholders' equity Liabilities and Equity Employee Stock Options Share-Based Payment Arrangement, Option [Member] Segments [Axis] Segments [Axis] Termination fee Business Combination, Parent Termination Fee Received Business Combination, Parent Termination Fee Received Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Plan Name [Axis] Plan Name [Axis] Income Tax Jurisdiction [Domain] Income Tax Jurisdiction [Domain] Tabular List, Table Tabular List [Table Text Block] Upfront payment received Proceeds From Sale Of Equity Method Investments, Upfront Payment Received Proceeds From Sale Of Equity Method Investments, Upfront Payment Received Additional paid-in capital Additional Paid in Capital Schedule of Share-based Compensation Share-Based Payment Arrangement, Cost by Plan [Table Text Block] Other income Other Nonoperating Income (Expense) License and Collaboration Agreements [Abstract] License and Collaboration Agreements Name Awards Close in Time to MNPI Disclosures, Individual Name Stockholders' equity Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Outstanding stock options, aggregate intrinsic value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period General and administrative General and Administrative Expense Sale of common stock, price per share (in dollars per share) Sale of Stock, Price Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, $0.0001 par value per share; 50,000,000 shares authorized as of June 30, 2026 and December 31, 2025; no shares issued or outstanding as of June 30, 2026 and December 31, 2025 Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Other receivables, gross, current Other Receivables, Gross, Current Net unrealized loss on marketable securities Marketable Security, Unrealized Gain (Loss) Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Avenzo Therapeutics, Inc Avenzo Therapeutics, Inc [Member] Avenzo Therapeutics, Inc RESTRUCTURING AND SEVERANCE Restructuring and Related Activities Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Fair value Assets, Fair Value Disclosure Income Tax Jurisdiction [Axis] Income Tax Jurisdiction [Axis] Name Measure Name Pre-Merger Equityholders of Avenzo Pre-Merger Equityholders of Avenzo [Member] Pre-Merger Equityholders of Avenzo Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Share pool increase, percentage of common shares outstanding Share Pool Increase, Percentage of Common Shares Outstanding Share Pool Increase, Percentage of Common Shares Outstanding Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] ADDITIONAL PAID-IN CAPITAL Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Aggregate fair value of available-for-sale debt securities in an unrealized loss position Debt Securities, Available-for-Sale, Unrealized Loss Position Follow on Offering Follow-On Offering [Member] Follow-on offering. Name Trading Arrangement, Individual Name Unrecognized share-based compensation expense, restricted stock units Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Cash and cash equivalents Cash and Cash Equivalent Company Selected Measure Amount Company Selected Measure Amount Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Future Milestone and Royalty Assets Future Milestone and Royalty Assets [Policy Text Block] Future Milestone and Royalty Assets Schedule of Stock by Class [Table] Stock, Class of Stock [Table] Measurement input Equity Securities, FV-NI, Measurement Input Current assets: Assets, Current [Abstract] Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Vested (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Income tax expense Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Expected volatility, minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Net income (loss) Net (loss) income Net income (loss) Net income (loss) Net Income (Loss) Attributable to Parent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Proceeds from the issuance of common stock from exercise of stock options Proceeds from Stock Options Exercised Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Exercisable stock options at end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Unaudited Financial Information Unaudited Financial Information [Policy Text Block] Unaudited Financial Instrument Concurrent Financing Concurrent Financing [Member] Concurrent Financing Revenue: Revenues [Abstract] Measurement Input, Discount for Lack of Marketability Measurement Input, Discount for Lack of Marketability [Member] RLYB116 RLYB116 [Member] RLYB116 Personnel expenses (including share-based compensation) Personal Expenses [Member] Personal Expenses SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES BASIS OF PRESENTATION AND PRINCIPLES OF CONSOLIDATION Basis of Presentation and Significant Accounting Policies [Text Block] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]