75000 - Document - Document and Entity Information
link:presentationLink
link:calculationLink
link:definitionLink
75010 - Statement - CONSOLIDATED BALANCE SHEETS (unaudited)
link:presentationLink
link:calculationLink
link:definitionLink
75020 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) (unaudited)
link:presentationLink
link:calculationLink
link:definitionLink
75030 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (unaudited)
link:presentationLink
link:calculationLink
link:definitionLink
75040 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (unaudited) 2
link:presentationLink
link:calculationLink
link:definitionLink
75050 - Statement - CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (unaudited)
link:presentationLink
link:calculationLink
link:definitionLink
75060 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited)
link:presentationLink
link:calculationLink
link:definitionLink
75070 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)
link:presentationLink
link:calculationLink
link:definitionLink
995455 - Disclosure - Nature of Business and Basis of Presentation
link:presentationLink
link:calculationLink
link:definitionLink
995465 - Disclosure - Summary of Significant Accounting Policies
link:presentationLink
link:calculationLink
link:definitionLink
995475 - Disclosure - Reorganization and Reverse Stock Split
link:presentationLink
link:calculationLink
link:definitionLink
995485 - Disclosure - Sale of Cullinan Pearl
link:presentationLink
link:calculationLink
link:definitionLink
995495 - Disclosure - Financial Instruments
link:presentationLink
link:calculationLink
link:definitionLink
995505 - Disclosure - Accrued Expenses and Other Current Liabilities
link:presentationLink
link:calculationLink
link:definitionLink
995515 - Disclosure - License and Collaboration Agreements
link:presentationLink
link:calculationLink
link:definitionLink
995525 - Disclosure - Cullinan-MICA Asset Acquisition
link:presentationLink
link:calculationLink
link:definitionLink
995535 - Disclosure - Stockholders' Equity
link:presentationLink
link:calculationLink
link:definitionLink
995545 - Disclosure - Equity-Based Compensation
link:presentationLink
link:calculationLink
link:definitionLink
995555 - Disclosure - Royalty Transfer Agreements
link:presentationLink
link:calculationLink
link:definitionLink
995565 - Disclosure - Income Taxes
link:presentationLink
link:calculationLink
link:definitionLink
995575 - Disclosure - Commitments and Contingencies
link:presentationLink
link:calculationLink
link:definitionLink
995585 - Disclosure - Leases
link:presentationLink
link:calculationLink
link:definitionLink
995595 - Disclosure - Employee Benefit Plan
link:presentationLink
link:calculationLink
link:definitionLink
995605 - Disclosure - Net Loss per Share
link:presentationLink
link:calculationLink
link:definitionLink
995615 - Disclosure - Segment Reporting
link:presentationLink
link:calculationLink
link:definitionLink
995625 - Disclosure - Subsequent Event
link:presentationLink
link:calculationLink
link:definitionLink
995635 - Disclosure - Summary of Significant Accounting Policies (Policies)
link:presentationLink
link:calculationLink
link:definitionLink
995645 - Disclosure - Summary of Significant Accounting Policies (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995655 - Disclosure - Reorganization and Reverse Stock Split (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995665 - Disclosure - Sale of Cullinan Pearl and Co-Development Agreement with Taiho (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995675 - Disclosure - Financial Instruments (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995685 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995695 - Disclosure - License and Collaboration Agreements (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995705 - Disclosure - Stockholders' Equity (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995715 - Disclosure - Equity-Based Compensation (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995725 - Disclosure - Leases (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995735 - Disclosure - Commitments and Contingencies (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995745 - Disclosure - Net Loss per Share (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995755 - Disclosure - Segment Reporting (Tables)
link:presentationLink
link:calculationLink
link:definitionLink
995765 - Disclosure - Nature of Business and Basis of Presentation - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995775 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995785 - Disclosure - Reorganization and Reverse Stock Split - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995795 - Disclosure - Reorganization and Reverse Stock Split - Number of Shares of Common Stock Exchanged and Issued to Unitholders on Split Adjusted Basis (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995805 - Disclosure - Reorganization and Reverse Stock Split - Summary of LLC Units Previously Reported as Redeemable Preferred Units or Temporary Equity Converted Reclassified to Equity (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995815 - Disclosure - Sale of Cullinan Pearl and Co-Development Agreement with Taiho - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995825 - Disclosure - Sale of Cullinan Pearl and Co-Development Agreement with Taiho - Schedule of cash consideration received (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995835 - Disclosure - Sale of Cullinan Pearl and Co-Development Agreement with Taiho - Parenthetical (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995845 - Disclosure - Financial Instruments - Schedule of Short-term and Long-term Investment Marketable Securities by Security Type (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995855 - Disclosure - Financial Instruments - Summary of Fair Value of Financial Assets Measured on Recurring Basis (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995865 - Disclosure - Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995875 - Disclosure - License and Collaboration Agreements - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995885 - Disclosure - License and Collaboration Agreements - Summary of Research and Development Costs Related to Collaboration and License Agreements (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995895 - Disclosure - Stockholders' Equity - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995905 - Disclosure - Stockholders' Equity - Schedule of Development Subsidiaries and Their Product Candidates (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995915 - Disclosure - Equity-Based Compensation - Schedule of Equity-based Compensation Expense Categories In Consolidated Statements of Operations and Comprehensive Income (Loss) (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995925 - Disclosure - Equity-Based Compensation - Schedule of Assumptions Used to Estimate Fair value of Market-Based RSUs Granted (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995935 - Disclosure - Royalty Transfer Agreements - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995945 - Disclosure - Income Taxes - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995955 - Disclosure - Commitment and Contingencies (Additional Information) (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995965 - Disclosure - Leases - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995975 - Disclosure - Leases - Supplemental Cash Flow Information Relating to Leases (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995985 - Disclosure - Leases - Summary of Future Minimum Payments Due Under Operating Lease (Details)
link:presentationLink
link:calculationLink
link:definitionLink
995995 - Disclosure - Leases - Summary of Future Minimum Payments Due Under Operating Lease (Details) 2
link:presentationLink
link:calculationLink
link:definitionLink
996005 - Disclosure - Leases - Summary of Weighted Average Remaining Lease Terms and Discount Rates (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996015 - Disclosure - Employee Benefit Plan - Additional Information (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996025 - Disclosure - Net Loss per Share - Summary of Calculation of Basic and Diluted Net Loss Per Share (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996035 - Disclosure - Net Loss per Share - Summary of Outstanding Equity Instruments Excluded from Computation of Diluted Net Loss Per Share (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996045 - Disclosure - Segment Reporting (Additional Information) (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996055 - Disclosure - Segment Reporting - Summary of Financial Information of Reportable Segment (Details)
link:presentationLink
link:calculationLink
link:definitionLink
996065 - Disclosure - Subsequent Event (Additional Information) (Details)
link:presentationLink
link:calculationLink
link:definitionLink
The disclosure of accrued expenses and other current liabilities.
Schedule Of Accrued Expenses And Other Current Liabilities Table [Text Block]
Summary of Accrued Expenses and Other Current Liabilities
License and collaboration agreements.
License And Collaboration Agreements [Line Items]
License And Collaboration Agreements [Line Items]
Due to Taiho under collaboration agreement, net
Due to Taiho under collaboration agreement, net
Due to Taiho under collaboration agreement, net
Entity Incorporation, State or Country Code
Entity Incorporation, State or Country Code
Preferred Stock, Share issued
Preferred Stock, Shares Issued
Preferred Stock, Shares Issued, Total
Shares issued
Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]
Summary of Fair Value of Financial Assets Measured on Recurring Basis
Junior preferred and common stockholders.
Junior Preferred And Common Stockholders [Member]
Junior Preferred and Common Stockholders
Increase (Decrease) in Accounts Payable
Accounts payable
Increase (Decrease) in Accounts Payable, Total
Revision of Prior Period [Axis]
Revision of Prior Period
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Non-cash investing and financing activities and supplemental cash flow information
Plan Name [Axis]
Plan Name
Entity Current Reporting Status
Entity Current Reporting Status
CLN-619 [Member]
CLN-619 [Member]
CLN-619 [Member]
Hypothetical liquidation at book value.
Hypothetical Liquidation At Book Value [Member]
HLBV
U.S. Government Notes
US Government Agencies Debt Securities [Member]
Sale of Cullinan Pearl
Sale Leaseback Transactions [Text Block]
Fair Value, Inputs, Level 2 [Member]
Level 2
Commitments and Contingencies Disclosure [Text Block]
Commitments and Contingencies
Common Stock, Shares Authorized
Common stock, shares authorized
Investment, Policy [Policy Text Block]
Investments
Document Fiscal Period Focus
Document Fiscal Period Focus
Entity Shell Company
Entity Shell Company
Capital Leases, Future Minimum Payments Due
Future minimum lease payments
Cash and cash equivalents
Cash and Cash Equivalent
Cash and Cash Equivalents, at Carrying Value, Total
Cash and Cash Equivalents, at Carrying Value, Beginning Balance
Cash and Cash Equivalents, at Carrying Value, Ending Balance
Stock Issued During Period, Shares, Conversion of Units
Number of Management's Shares Issued
Common Stock, Shares, Issued
Common Stock, Shares, Issued, Total
Shares sold/issued
Common Stock, Shares Issued
Statement [Table]
Statement [Table]
Number of development subsidiaries.
Number Of Development Subsidiaries
Number of development subsidiaries
Consulting fee.
Consulting Fee
Consulting fee
Genrix Biopharmaceutical Co, Ltd [Member]
Genrix Biopharmaceutical Co, Ltd [Member]
Genrix Biopharmaceutical Co, Ltd
Right-of-use asset obtained in exchange for an operating lease liability
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability
Operating Income (Loss) [Abstract]
Operating expenses:
Financial Support to Nonconsolidated Legal Entity [Axis]
Financial Support to Nonconsolidated Legal Entity
Statement [Line Items]
Statement [Line Items]
Operating lease rentable area.
Operating Lease Rentable Area
Operating lease rentable area
Warrant [Member]
Warrant
Entity Filer Category
Entity Filer Category
Liabilities and Equity
Total liabilities and stockholders' equity
Accounting Standards Update and Change in Accounting Principle [Table Text Block]
Summary of LLC Units Previously Reported as Redeemable Preferred Units or Temporary Equity Converted Reclassified to Equity
Cash, cash equivalents, short-term investments and long-term investments.
Cash Cash Equivalents Short Term Investments And Long Term Investments
Cash, cash equivalents, short-term investments and long-term investments
Financial Instruments
Financial Instruments Disclosure [Text Block]
Cash and Cash Equivalents, Fair Value Disclosure
Total cash and cash equivalents
Subsequent Event [Line Items]
Total identifiable net assets sold
Identifiable Net Assets Sold
Identifiable Net Assets Sold
Expected dividend yield
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Weighted Average Expected Dividend
Stock Options
Investment Income, Interest
Interest income
Geographical [Domain]
Geographical
Long term investments fair value disclosure.
Long Term Investments Fair Value Disclosure
Total long-term investments
Asset-backed Securities
Asset-Backed Securities [Member]
Expenditures for Long-Lived Assets
Segment, Expenditure, Addition to Long-Lived Assets
Additional Paid in Capital, Common Stock, Ending Balance
Additional Paid in Capital, Common Stock
Additional paid-in capital
Additional Paid in Capital, Common Stock, Beginning Balance
Zipalertinib [Member]
Zipalertinib
Zipalertinib [Member]
Defined Contribution Plan [Text Block]
Employee Benefit Plan
Significant Accounting Policies [Text Block]
Summary of Significant Accounting Policies
Accounts Payable and Accrued Liabilities, Current [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Summary of Calculation of Basic and Diluted Net Loss Per Share
Dividends Payable
Dividends declared
Net loss per share, basic
Basic
Earnings Per Share, Basic
Earnings Per Share, Basic, Total
Liabilities, Current
Total current liabilities
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Adjustments to reconcile net loss to net cash used in operating activities:
Total accrued expenses and other current liabilities
Accrued expenses and other current liabilities.
Accrued Expenses And Other Current Liabilities
At-the-Market Equity Offering Program [Member]
At-the-Market Equity Offering Program [Member]
At-the-Market Equity Offering Program
Consolidation Items [Domain]
Equity, Attributable to Parent [Abstract]
Stockholders' Equity (Members' Deficit)
Entity Small Business
Entity Small Business
Retained Earnings (Accumulated Deficit)
Retained Earnings (Accumulated Deficit), Total
Retained Earnings (Accumulated Deficit), Beginning Balance
Retained Earnings (Accumulated Deficit), Ending Balance
Accumulated deficit
Financial Support to Nonconsolidated Legal Entity [Domain]
Financial Support to Nonconsolidated Legal Entity
Preferred Stock
Preferred Stock [Member]
Proceeds from Issuance Initial Public Offering
Proceeds from initial public offering
Net proceeds
Income tax provision
Income Tax Provision
Income tax provision
Share-Based Payment Arrangement [Text Block]
Equity-Based Compensation
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Leases [Abstract]
Lessee, Lease, Description [Line Items]
Lessee Lease Description [Line Items]
Amendment Flag
Amendment Flag
Loss Contingencies [Line Items]
Cullinan MICA Corp.
Cullinan M I C A Corp [Member]
MICA
MICA
Earnings Per Share, Policy [Policy Text Block]
Net Loss per Share
Liabilities and Stockholders' Equity
Liabilities and Equity [Abstract]
Entity Address, Postal Zip Code
Entity Address, Postal Zip Code
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation
Net cash used in operating activities
Common Stock
Common Stock [Member]
Sales Based [Member]
Sales Based [Member]
Gain on sale of Cullinan Pearl
Gain on sale of Cullinan Pearl
Gain on disposition of non-financial assets
Gain( Loss) On Disposition Of Non Financial Assets
Gain( Loss) On Disposition Of Non Financial Assets.
Collaborative Arrangement and Arrangement Other than Collaborative [Table Text Block]
Summary of Research and Development Costs Related to Collaboration and License Agreements
Lessee, Operating Lease, Liability, to be Paid, Year Three
2027
Cash
net of cash transferred
Cash Transferred with Sale
Cash transferred with sale.
Estimated shares issuable under the ESPP.
Estimated Shares Issuable Under E S P P [Member]
Employee stock purchase plan
Entity Address, Address Line One
Entity Address, Address Line One
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Schedule of Assumptions Used to Estimate Fair value of Market-Based RSUs Granted
Fair Value Hierarchy and NAV [Axis]
Fair Value Hierarchy and NAV
Earnings Per Share [Abstract]
Basic and diluted net loss per share attributable to Cullinan:
Income Tax, Policy [Policy Text Block]
Income Taxes
Temporary Equity, Carrying Amount, Attributable to Parent
Total Redeemable Preferred Units
Supplemental Cash Flow Information [Abstract]
SUPPLEMENTAL NONCASH DISCLOSURE
Amounts Attributable To Liabilities Sold
Amounts Attributable To Liabilities Sold
Amounts attributable to liabilities sold
Investment Type [Axis]
Investment Type
Operating Lease, Right-of-Use Asset
Operating lease right-of-use assets
Net loss attributable to noncontrolling interests
Net Income (Loss) Attributable to Noncontrolling Interest
Losses attributed to noncontrolling interests
Net Income (Loss) Attributable to Noncontrolling Interest, Total
Payments to Acquire Debt Securities, Available-for-Sale
Purchase of marketable securities
Purchase of marketable securities
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax, Total
Unrealized gain (loss) on investments
Unrealized gain (loss) on investments
Unrealized loss on investments
Percentage of profits from potential sales
Percentage of Profits from Potential Sales
Percentage of profits from potential sales.
Document Type
Document Type
Other segment expenses
Other segment expenses
Other segment expenses
Income Taxes Paid, Net, Total
Income Taxes Paid, Net
Cash refunded for income taxes
Collaborative Arrangement and Arrangement Other than Collaborative [Axis]
Collaborative Arrangement and Arrangement Other than Collaborative
Subsidiary, Ownership Percentage, Parent
Subsidiary, Ownership Percentage
Collaborative Arrangement and Arrangement Other than Collaborative [Domain]
Entity Central Index Key
Entity Central Index Key
Entity Central Index Key
Debt Securities, Available-for-Sale [Table Text Block]
Schedule of Short-term and Long-term Investment Marketable Securities by Security Type
Achievement Based [Member]
Achievement Based [Member]
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation
Net increase in cash and cash equivalents
Subsequent Event Type [Domain]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Equity instruments excluded from computation of diluted net loss per share (in shares)
Increase in number of shares of preferred stock, percentage
Increase in Number of Shares of Preferred Stock, Percentage
Increase in number of shares of preferred stock, percentage
License and collaboration agreements.
License And Collaboration Agreements [Abstract]
Impairment of long-lived assets
Impairment of long-lived assets
Impairment of Long-Lived Assets to be Disposed of
Common Stock, Par or Stated Value Per Share
Common stock, par value
Reorganization and reserve stock split.
Reorganization And Reverse Stock Split [Abstract]
Operating Lease Payments Proceeds
Operating Lease Payments Proceeds
Operating cash flows from operating leases
Debt Securities, Available-for-Sale, Amortized Cost
Amortized Cost
Debt Securities, Available-for-Sale
Estimated Fair Value
Debt Securities, Available-for-sale, Total
Indemnification Agreement [Member]
Accrued Liabilities, Current
Accrued expenses and other current liabilities
Accrued Liabilities, Current, Total
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Ownership [Domain]
Current Fiscal Year End Date
Current Fiscal Year End Date
Acquisition of noncontrolling interests
Acquisition of noncontrolling interests
Payments to Noncontrolling Interests
Royalty percentage.
Royalty Percentage
Royalty percentage
Reorganization and reserve stock split.
Reorganization And Reverse Stock Split [Table]
Reorganization And Reverse Stock Split [Table]
Document Quarterly Report
Document Quarterly Report
MOROCCO
Massachusetts
Sublease Agreement [Member]
Sublease Agreement [Member]
Sublease Agreement [Member]
Preferred Stock, Shares Outstanding
Preferred Stock, Shares Outstanding, Ending Balance
Preferred Stock, Shares Outstanding, Beginning Balance
Preferred stock, Share Outstanding
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Comprehensive loss attributable to Cullinan
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Gross Unrealized Gains
Research and Development Expense, Policy [Policy Text Block]
Research and Development Expenses
Geographical [Axis]
Geographical
Equity, Attributable to Noncontrolling Interest
Noncontrolling interests
Non-controlling interests in subsidiaries
Stockholders' Equity Attributable to Noncontrolling Interest, Total
Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance
Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
Schedule of Equity-based Compensation Expense Categories In Consolidated Statements of Operations and Comprehensive Income (Loss)
Additional receive payments from the party
Additional receive payments from the party
Accrued Bonuses, Current
Employee compensation
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]
Accrued Expenses and Other Current Liabilities
Schedule of cash consideration received
Schedule of Cash Consideration Received Table Text Block
Schedule of Cash Consideration Received Table Text Block
Maturities of marketable securities
Proceeds from Sale and Maturity of Marketable Securities
Proceeds from Sale and Maturity of Marketable Securities, Total
Subsequent Event [Member]
Subsequent Event [Member]
Other Assets, Noncurrent
Other assets
Other Assets, Noncurrent, Total
Issuance of Common Stock Upon Conversion of Preferred Stock
Issuance of common stock upon conversion of preferred stock, Shares
Issuance of common stock upon conversion of preferred stock, Share
R&D personnel and operations
R&D personnel and operations
R&D personnel and operations
Antidilutive Securities [Axis]
Antidilutive Securities
Cullinan [Member]
Cullinan [Member]
Cullinan [Member]
Nature of Business and Basis of Presentation.
Nature Of Business And Basis Of Presentation [Table]
Nature Of Business And Basis Of Presentation [Table]
Related Party Transaction [Axis]
Related Party Transaction
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent [Member]
Cash [Member]
Cash
Cash and Cash Equivalents [Domain]
Cash and Cash Equivalents
Cash Flow, Operating Capital [Table Text Block]
Supplemental Cash Flow Information Relating to Leases
Amortization accretion on marketable securities.
Amortization Accretion On Marketable Securities
Accretion on marketable securities
Preferred Stock, Value, Issued
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of March 31, 2026 and December 31, 2025; 481,989 and 555,935 shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively.
Cullinan Pearl Corp.
Cullinan Pearl Corp [Member]
Cullinan Pearl Corp
Minimum [Member]
Minimum
Financial Instrument [Axis]
Financial Instrument
Assets, Current [Abstract]
Current assets:
Defined Contribution Plan, Administrative Expense
Expense relating to matching contribution
License and collaboration agreements.
License And Collaboration Agreements [Table]
License And Collaboration Agreements [Table]
Operating lease commence date.
Operating Lease Commence Date
Operating lease commence date
Other Long-Term Investments
Long Term Investments
Long-term investments and interest receivables
Accrued expenses and other current liabilities
Accounts Payable and Other Accrued Liabilities, Current
Fair Value, Inputs, Level 3 [Member]
Level 3
Segment Reporting [Abstract]
Patent costs.
Patent Costs Policy [Text Block]
Patent Costs
Liabilities, Current [Abstract]
Current liabilities:
Reorganization And Reserve Stock Split.
Reorganization And Reverse Stock Split [Line Items]
Reorganization And Reverse Stock Split [Line Items]
Royalty Transfer Agreements [Abstract]
Amount of Carrying Value in Excess of Fair Value
Reporting Unit, Amount of Fair Value in Excess of Carrying Amount
Shares, Outstanding
Number of shares outstanding
Balances, shares Begning
Balances, shares Ending
Sublease Income
Sublease income
Commitments and Contingencies
Commitments and contingencies (Note 8)
Lessee, Leases [Policy Text Block]
Leases
General and Administrative Expense [Member]
General and Administrative
Cullinan Oncology, LLC.
Cullinan Oncology L L C [Member]
Cullinan Oncology, LLC
Cullinan Oncology, LLC
Operating Lease, Liability
Total lease liabilities at present value
Total lease liabilities at present value
MPM Oncology Charitable Foundation, Inc.
M P M Oncology Charitable Foundation Inc [Member]
MPM Oncology Charitable Foundation, Inc.
Series C redeemable preferred units.
Series C Redeemable Preferred Units [Member]
Series C Redeemable Preferred Units
Globeways Holdings Limited.
Globeways Holdings Limited [Member]
Globeways Holdings Limited
Lessee, Lease, Description [Table]
Lessee Lease Description [Table]
Liabilities, Noncurrent [Abstract]
Long-term liabilities:
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest
Net Income (loss)
Net Loss
Net loss
Net loss
Increase decrease in accrued expenses and other current liabilities.
Increase Decrease In Accrued Expenses And Other Current Liabilities
Accrued expenses and other liabilities
Debt Securities, Available-for-Sale, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract]
Rule 10b5 1 Arr Modified Flag
Rule 10b5-1 Arrangement Modified
Rule 10b5-1 Arrangement Modified [Flag]
Share-Based Payment Arrangement, Recognized Amount [Abstract]
Long-Term Debt, Type [Domain]
Long-term Debt, Type
Loss Contingencies [Table]
Basic
Weighted Average Number of Shares Outstanding, Basic
Weighted Average Number of Shares Outstanding, Basic, Total
Weighted-average shares outstanding - basic
Pearl - Taiho Pharma.
Pearl Taiho Pharma [Member]
Pearl - Taiho
Scenario [Axis]
Series Seed Preferred Units.
Series Seed Preferred Units [Member]
Series Seed Preferred Units
Temporary Equity [Abstract]
Redeemable Preferred Units
Scenario, Adjustment [Member]
Noncontrolling interests.
Noncontrolling Interests Policy [Text Block]
Noncontrolling Interests
Stock Issued During Period, Shares, Reverse Stock Splits
Adjusted for the Reverse Stock Split
Proceeds from Issuance of Private Placement
Net Cash Proceeds from 2024 Private Placement
Subsequent Events [Text Block]
Subsequent Event
Royalty Transfer Agreements
Related Party Transactions Disclosure [Text Block]
Cash
Equity, Attributable to Parent
Total Cullinan stockholders' equity
Total Cullinan Stockholders' Equity (Members' Deficit)
Stockholders' Equity Attributable to Parent, Beginning Balance
Stockholders' Equity Attributable to Parent, Ending Balance
Preferred Stock par value
Preferred Stock, Par or Stated Value Per Share
Basis of Accounting, Policy [Policy Text Block]
Basis of Presentation
Statement of Stockholders' Equity [Abstract]
Corporate Note Securities [Member]
Corporate Note Securities
Series C Preferred Stock [Member]
Series C Preferred Units
Series A Preferred Stock [Member]
Series A Preferred Stock
Use of Estimates, Policy [Policy Text Block]
Use of Estimates
Long term investment.
Long Term Investment [Member]
Long Term Investment
Collaborative Arrangement [Member]
Collaboration Agreements
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Disclosure [Line Items]
Over-Allotment Option [Member]
Underwriters' Option
Entity Address, Address Line Two
Entity Address, Address Line Two
Upfront consideration, inclusive of cash transferred of $2,898
Subsidiary or Equity Method Investee, Cumulative Proceeds Received on All Transactions
Number of shares of common stock, percentage
Number of Shares of Common Stock, Percentage
Number of shares of common stock, percentage
Noncontrolling Interest [Member]
Noncontrolling Interest
Available for sale securities fair value to amortized cost basis.
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Plan Name [Domain]
Plan Name
Two thousand twenty consulting agreement.
Two Thousand Twenty Consulting Agreement [Member]
2020 Consulting Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Entity [Domain]
Entity
Summarizes Lease Term and Discount Rate Table Text Block
Summarizes Lease Term and Discount Rate Table Text Block
Summarizes Lease Term and Discount Rate
Business Description and Basis of Presentation [Text Block]
Nature of Business and Basis of Presentation
Schedule of development subsidiaries and their product candidates
Schedule of development subsidiaries and their product candidates
Schedule of Development Subsidiaries and Their Product Candidates
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
Issuance of common stock and pre-funded warrants, Shares
Issuance of common stock and pre-funded warrants net of issuance costs, Shares
Issuance of Common Stock and Pre Funded Warrants Net of Issuance Costs,Shares
Issuance of Common Stock and Pre Funded Warrants Net of Issuance Costs,Shares
Related and Nonrelated Parties [Axis]
Related Party
Asset Acquisition [Text Block]
Cullinan-MICA Asset Acquisition
Issuance of common stock and pre-funded warrants, net of issuance costs
Issuance of common stock and pre-funded warrants, net of issuance costs
Issuance Of Common Stock And Pre Funded Warrants Net Of Issuance Costs
Issuance Of Common Stock And Pre Funded Warrants Net Of Issuance Costs
Net of escrow
Net of escrow
Net of escrow
Adimab.
Adimab [Member]
Adimab
Non Voting Incentive Units [Member]
Non-Voting Incentive Units
Non Voting Incentive Units Member
Entity Address, City or Town
Entity Address, City or Town
Available For Sale Securities Fair Value To Amortized Cost Basis.
Available For Sale Securities Fair Value To Amortized Cost Basis [Table]
Available For Sale Securities Fair Value To Amortized Cost Basis [Table]
License agreement between amber and Massachusetts institute of technology.
License Agreement Between Amber And Massachusetts Institute Of Technology [Member]
License Agreement between Amber and Massachusetts Institute of Technology
Number of Reportable Segments
Number of reportable segments
Security Exchange Name
Security Exchange Name
Series A1 redeemable preferred units.
Series A1 Redeemable Preferred Units [Member]
Series A1 Redeemable Preferred Units
Offering costs
Deferred Offering Costs
Pearl Zai lab license agreement.
Pearl Zai Lab License Agreement [Member]
Pearl—Zai Lab License Agreement
UBS Optimus Foundation.
U B S Optimus Foundation [Member]
UBS Optimus Foundation
Antidilutive Securities, Name [Domain]
Antidilutive Securities, Name
Stockholders' Equity Note [Abstract]
Series seed redeemable preferred units.
Series Seed Redeemable Preferred Units [Member]
Series Seed Redeemable Preferred Units
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]
Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table]
Statistical Measurement [Domain]
Statistical Measurement
Assets, Current
Total current assets
Share-Based Payment Arrangement, Expense
Total equity-based compensation
Noncash or Part Noncash Acquisition, Fixed Assets Acquired
Purchases of property and equipment included in accounts payable and accrued expenses and other liabilities
Document Period End Date
Document Period End Date
Net of escrow
Payment held in escrow
Escrow Deposits Related to Property Sales
Fair Value Hierarchy and NAV [Domain]
Fair Value Hierarchy and NAV
Nature of business and basis of presentation.
Nature Of Business And Basis Of Presentation [Line Items]
Nature Of Business And Basis Of Presentation [Line Items]
Statement of Financial Position [Abstract]
Loss Contingency Nature [Axis]
Revenue [Policy Text Block]
Revenue Recognition
Loss Contingency, Nature [Domain]
Antidilutive Security, Excluded EPS Calculation [Table]
Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table]
Class of Stock [Axis]
Class of Stock
Liabilities
Total liabilities
Financial Instruments [Domain]
Financial Instruments
Operating Lease, Lease Income, Lease Payments
Lease Payments
Lessee, Operating Lease, Liability, to be Paid, Year Two
2023
2028
MIT
Massachusetts Institute of Technology [Member]
Massachusetts institute of technology [Member]
Restricted Stock [Member]
Restricted stock units
Diluted
Weighted Average Number of Shares Outstanding, Diluted
Weighted Average Number of Shares Outstanding, Diluted, Total
Weighted-average shares outstanding - diluted
Securities Act File Number
Entity File Number
Line Items represent common stock and Noncontrolling Interest in subsidiaries.
Common Stock And Noncontrolling Interest In Subsidiaries [Line Items]
Common Stock And Noncontrolling Interest In Subsidiaries [Line Items]
Deferred offering costs.
Deferred Offering Costs Policy [Text Block]
Deferred Offering Costs
Accrued Expenses And Other Current Liabilities.
Accrued Expenses And Other Current Liabilities [PolicyTextBlock]
Accrued Expenses and Other Current Liabilities
Cover [Abstract]
DFKZ and UFE anti-dilution shares.
D F K Z And U F E Anti Dilution Shares [Member]
DFKZ and UFE Anti-dilution Shares
G&A personnel and operations
G&A personnel and operations
General and Administrative personnel
General and administrative personnel
Prepaid expenses and other current assets
Prepaid Expense and Other Assets, Current
Investments [Domain]
Investments
Scenario [Domain]
Number of operating segments
Number of Operating Segments
Sale of Stock [Domain]
Sale of Stock
Segment Reporting Disclosure [Text Block]
Segment Reporting
General and Administrative Expense
General and Administrative Expense, Total
General and administrative Cost
General and administrative expense
Series B Preferred Stock [Member]
Series B Preferred Units
Subsequent Event [Table]
Milestone payments
Milestone Payments
Milestone payments
Short-Term Debt, Type [Domain]
Short-term Debt, Type
Operating Lease expense
Operating Lease, Expense
Short-term investments.
Short Term Investment [Member]
Short Term Investments
Short-term Debt, Type
Short-Term Debt, Type [Axis]
New Accounting Pronouncements, Policy [Policy Text Block]
Recently Issued Accounting Pronouncements
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]
Summary of Future Minimum Payments Due Under Operating Lease
Summarizes of Future Minimum Lease Payments
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Ownership [Axis]
Reorganization and reverse stock split.
Reorganization And Reverse Stock Split [Text Block]
Reorganization and Reverse Stock Split
Consideration received
Disposal Group, Including Discontinued Operation, Consideration
Schedule reflecting common stock and noncontrolling interest in subsidiaries.
Common Stock And Noncontrolling Interest In Subsidiaries [Table]
Common Stock And Noncontrolling Interest In Subsidiaries [Table]
Long-Term Investments
Long-term investments
Long-term Investments, Total
Common Stock, Shares, Outstanding
Common stock, shares outstanding
Common Stock, Shares, Outstanding, Beginning Balance
Common Stock, Shares, Outstanding, Ending Balance
Operating Lease, Liability, Current
Operating lease liabilities, current
Lease liabilities, current
Depreciation, Depletion and Amortization
Depreciation and amortization
Depreciation, Depletion and Amortization, Total
Biotechnology Value Fund, L.P exchange agreement [Member]
Biotechnology Value Fund, L.P exchange agreement
CLN-617 [Member]
CLN-617 [Member]
CLN-617 [Member]
Document Transition Report
Document Transition Report
Short-Term Investments
Short-term investments
Short-term Investments, Total
Operating Expenses
Total operating expenses
Research and Development Expense
Research and development costs
Research and development
Total R&D program expense
Lessee, Operating Leases [Text Block]
Leases
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest
Comprehensive loss
Statement of Cash Flows [Abstract]
Stock Issued During Period, Value, New Issues
Issuance of common stock under equity-based compensation plans
Stockholders' Equity
Equity [Text Block]
Cullinan amber corp.
Cullinan Amber Corp [Member]
Cullinan Amber Corp
Earnings Per Share [Text Block]
Net Loss per Share
Net loss - basic and diluted
Net loss
Note Purchase Agreement [Member]
Note Purchase Agreement [Member]
Note Purchase Agreement
Short term investments fair value disclosure.
Short Term Investments Fair Value Disclosure
Total short-term investments
Expected dividend yield
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate
Harbour License Agreement [Member]
Harbour License Agreement [Member]
Harbour License Agreement
Assets [Abstract]
Assets
Risk-free interest rate
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate
Increase (Decrease) in Prepaid Expense and Other Assets
Increase (Decrease) in Prepaid Expense and Other Assets, Total
Prepaid expenses and other assets
Document Fiscal Year Focus
Document Fiscal Year Focus
Earnings Net loss Per Share
Earnings net loss per share
Net loss per share:
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
Investing activities:
Retirement Benefits [Abstract]
Accounts Payable, Current
Accounts payable
Accounts Payable, Current, Total
Research and Development Expense [Member]
Research and Development
Taiho [Member]
Taiho [Member]
Taiho [member]
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture
Equity-based compensation
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture, Total
Percentage of Independent Development Costs
Percentage of Independent Development Costs
Percentage of Independent Development Costs
Jennifer Michaelson [Member]
Jennifer Michaelson [Member]
Jennifer Michaelson
Book Value of Asset Sold [Abstract]
Book Value of Asset Sold.
Revision of Prior Period [Domain]
Revision of Prior Period
Summary of details of number of shares of common stock exchanged and Issued.
Summary Of Details Of Number Of Shares Of Common Stock Exchanged And Issued Table [Text Block]
Number of Shares of Common Stock Exchanged and Issued to Unitholders on Split Adjusted Basis
Fair Value Disclosures [Abstract]
Commitments and Contingencies Disclosure [Abstract]
Lessee, Operating Lease, Liability, to be Paid, Year One
2022
2027
Rent expense under the prior lease accounting standard
Operating Leases, Rent Expense
General and administrative expense related to share of costs
General and administrative expense related to share of costs.
General And Administrative Expense Related To Share Of Costs
Share-Based Payment Arrangement [Abstract]
Debt Securities, Available-for-Sale [Abstract]
Assets, Fair Value Disclosure
Total cash, cash equivalents and investments
Assets Fair Value Disclosure, Total
Sale of Stock [Axis]
Sale of Stock
Research and Development Expenses [domain]
Research and Development Expenses [domain]
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation
Net cash provided by (used in) investing activities
Private Placement [Member]
2024 Private Placement
Title of 12(b) Security
Title of 12(b) Security
Schedule of Segment Reporting Information, by Segment [Table]
Money Market Funds
Money Market Funds [Member]
Related and Nonrelated Parties [Domain]
Related Party
Earnings Per Share, Basic, Other Disclosure [Abstract]
Weighted-average shares used in computing basic and diluted net loss per share attributable to Cullinan:
Income Tax Disclosure [Text Block]
Income Taxes
Remainder of 2022
Remainder of 2023
Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year
Remainder of 2026
Consolidated Entities [Axis]
Consolidated Entities
Legal Entity [Axis]
Legal Entity
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Changes in operating assets and liabilities:
Income Tax Disclosure [Abstract]
Fair Value, Recurring and Nonrecurring [Table]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]
Additional Paid-In Capital
Additional Paid-in Capital [Member]
Measurement Frequency [Domain]
Measurement Frequency
Upfront license fee
Upfront License Fee
Upfront License Fee
Statement of Income Location, Balance [Axis]
Income Statement Location
Trading Symbol
Trading Symbol
Related Party Transaction [Table]
Schedule Of Related Party Transactions By Related Party [Table]
CLN-978 [Member]
CLN-978 [Member]
CLN-978 [Member]
Subsequent Event Type [Axis]
Amounts attributable to assets sold
Amounts Attributable to Assets Sold
Amounts Attributable to Assets Sold
Revision of Prior Period, Adjustment [Member]
Adjustment
Financial Instruments Pledged as Collateral [Abstract]
Book Value Of Liability Sold [Abstract]
Book Value Of Liability Sold.
Common Stock and Noncontrolling Interest in Subsidiaries [Abstract]
Common Stock And Noncontrolling Interest In Subsidiaries [Abstract]
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
Financing activities:
Expected term (in years)
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term
Fair Value, Recurring [Member]
Recurring
Entity Ex Transition Period
Entity Ex Transition Period
Total future minimum lease payments
Lessee, Operating Lease, Liability, to be Paid
Lessee, Operating Lease, Liability, Undiscounted Excess Amount
Less: Imputed Interest
Less: imputed interest
Equity Components [Axis]
Equity Components
Equity Component [Domain]
Equity Component
Non Rule 10b5 1 Arr Modified Flag
Non Rule 10b5-1 Arrangement Modified
Non-Rule 10b5-1 Arrangement Modified [Flag]
IPO [Member]
IPO
Issuance of common stock under equity-based compensation plans
Net issuance of common stock under equity-based compensation plans, shares
Stock Issued During Period, Shares, Employee Stock Purchase Plans
Subsidiaries [Member]
Common Stock, Voting Rights
Common stock, voting rights
Early-stage programs [Member]
Early-stage programs [Member]
Early-stage programs [Member
Maximum [Member]
Maximum
Statistical Measurement [Axis]
Statistical Measurement
Prepaid Expense, Current
Prepaid expenses and other current assets
Prepaid Expense, Current, Total
Common Stock, Value, Issued
Common Stock
Common Stock, Value, Issued, Total
Common Stock, Value, Issued, Beginning Balance
Common Stock, Value, Issued, Ending Balance
Common stock, $0.0001 par value, 150,000,000 shares authorized as of March 31, 2026 and December 31, 2025; 61,451,380 and 60,244,136 shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively
CLN-049 [Member]
CLN-049 [Member]
CLN-049 [Member]
Consolidation, Policy [Policy Text Block]
Principles of Consolidation
Accrued expenses and other current liabilities.
Accrued Expenses And Other Current Liabilities [Abstract]
Equity, Including Portion Attributable to Noncontrolling Interest
Total stockholders' equity
Total Stockholders' Equity (Members' Deficit)
Balances Ending
Balances Begning
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Comprehensive income (loss):
Receive upfront payment from party
Receive upfront payment from party
Upfront payment
Receive upfront payment from party
Accrued Liabilities, Total
Accrued Liabilities
Accrued liabilities
Upfront consideration, cash transferred
Upfront Consideration, Cash Transferred
Upfront Consideration, Cash Transferred
401(k) Plan).
Four Zero One K Plan [Member]
401(K) Plan
Milestones Parameter [Axis]
Milestones Parameter [Axis]
Impairment of long-lived assets
Impairment of Long-lived Assets
Impairment of Long-lived Assets
Impairment of long-lived assets
Other Nonoperating Income (Expense) [Abstract]
Other income (expense):
Expected volatility
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate
Preferred Stock, shares authorized
Preferred Stock, Shares Authorized
Royalty Expense
Royalties under obligation
Comprehensive loss attributable to noncontrolling interests
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Total
Long term investments and interest receivable.
Long Term Investments And Interest Receivable
Long-term investments and interest receivable
Related Party Transaction, Description of Transaction
Related party transaction, description of transaction
Royalty Transfer Agreements [Member]
Royalty Transfer Agreements [Member]
Repayment of convertible note
Repayment of convertible notes
Repayments of Convertible Debt
Related Party Transaction [Line Items]
Related Party Transaction [Line Items]
Entity Registrant Name
Entity Registrant Name
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax
Gross Unrealized Losses
Sales Agreement [Member]
Sales Agreement [Member]
Sales Agreement [Member]
Other Nonoperating Income (Expense)
Other Nonoperating Income (Expense), Total
Other income (expense), net
Other expense, net
Subsequent Events [Abstract]
Consolidated Entities [Domain]
Consolidated Entities
Income tax expense (benefit)
Income Tax Expense (Benefit)
Income Tax Expense (Benefit), Total
Income tax expense/(benefit)
Income tax expense
Consulting fee per month.
Consulting Fee Per Month
Consulting fee per month
Measurement Frequency
Measurement Frequency [Axis]
Issuance of Common Stock Upon Exercise of Pre-funded Warrants
Issuance of Common Stock Upon Exercise of Pre-funded Warrants
Proceeds from Issuance of Common Stock
Issuance of common stock and pre-funded warrants, net of issuance costs
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Lessee, Operating Lease, Remaining Lease Term
Operating Lease Term
Accumulated Other Comprehensive Income (Loss), Net of Tax
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total
Accumulated other comprehensive income (loss)
Consolidation Items [Axis]
Non-voting incentive units.
Non Voting Incentive Units
Non-Voting Incentive Units
Payments to Acquire Property, Plant, and Equipment
Payments to Acquire Property, Plant, and Equipment, Total
Purchases of property and equipment
Purchases of property and equipment
Harbour BioMed US Inc. [Member]
Harbour BioMed US Inc. [Member]
Harbour BioMed US Inc.
Assets
Total assets
Income Statement [Abstract]
Retirement Plan Name [Domain]
Retirement Plan Name
Fair Value of Financial Instruments, Policy [Policy Text Block]
Fair Value of Financial Instruments
Cullinan Florentine Corp.
Cullinan Florentine Corp [Member]
Cullinan Florentine Corp
Share-Based Payment Arrangement [Policy Text Block]
Equity-based Compensation
May Thirty One Two Thousend Thirty Three [Member]
May Thirty One Two Thousend Thirty Three [Member]
In May 2023
Common Units.
Common Units [Member]
Common Units
Issuance of common stock under equity-based compensation plans
Stock Issued During Period, Shares, New Issues
Issuance of common stock under equity-based compensation plans, Shares
Series A senior preferred stock.
Series A Senior Preferred Stock [Member]
Series A Senior Preferred Stock
Net loss per share, diluted
Diluted
Earnings Per Share, Diluted
Earnings Per Share, Diluted, Total
Financial Information of Reportable Segment
Schedule of Segment Reporting Information, by Segment [Table Text Block]
Operating Segments [Member]
Operating Segments [Member]
Series B redeemable preferred units.
Series B Redeemable Preferred Units [Member]
Series B Redeemable Preferred Units
City Area Code
City Area Code
RecievablesFromRelatedParty
Recievables From Related Party
Recievables From Related Party
Accrued research and development costs.
Accrued Research And Development Costs
Contracted research and development expenses
Defined Benefit Plan [Table]
Schedule Of Defined Benefit Plans Disclosures [Table]
Stock Issued During Period, Value, Employee Stock Purchase Plan
Issuance of common stock under equity-based compensation plans
Operating Lease, Weighted Average Remaining Lease Term
Weighted-average remaining lease term (in years)
Segment Reporting Information [Line Items]
Stockholders' Equity Note, Stock Split, Conversion Ratio
Reverse stock split conversion ratio
Investor [Member]
Other Existing Investors
Lease Expiration Date
Operating lease expiration date
Retirement Plan Name [Axis]
Retirement Plan Name
Award Date [Axis]
Cash and Cash Equivalents, Policy [Policy Text Block]
Cash and Cash Equivalents
Supplemental Balance Sheet Information Related To Operating Leases.
Supplemental Balance Sheet Information Related To Operating Leases [TableTextBlock]
Supplemental Balance Sheet Information Related to Operating Leases
Velinotamig [Member]
Velinotamig [Member]
Property, Plant and Equipment, Net
Property and equipment, net
Property, Plant and Equipment, Net, Total
Property, Plant and Equipment, Net, Beginning Balance
Property, Plant and Equipment, Net, Ending Balance
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation
Cash and cash equivalents at end of period
Cash and cash equivalents at beginning of period
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total
Operating Income (Loss)
Loss from operations
Loss from operations
Award Date [Domain]
Research and development expense related to share of costs
Research and Development Expense Related to Share of Costs.
Research and Development Expense Related to Share of Costs
Accumulated Deficit
Retained Earnings [Member]
Entity Address, Country
Entity Address, Country
Cash and Cash Equivalents [Axis]
Cash and Cash Equivalents
Share-Based Payment Arrangement, Noncash Expense
Equity-based compensation expense
Share-based Payment Arrangement, Noncash Expense, Total
Equity-based compensation
Proceeds from net issuance of common stock under equity-based compensation plans
Proceeds from net issuance of common stock under equity-based compensation plans
Issuance of common stock under equity-based compensation plans
Operating Lease, Weighted Average Discount Rate, Percent
Weighted-average discount rate
Operating lease liabilities, net of current portion
Operating Lease, Liability, Noncurrent
Noncurrent portion of operating lease liabilities
Fair Value, Inputs, Level 1 [Member]
Level 1
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation
Net cash provided by financing activities
Cash Equivalents Short Term Investments And Interest recivable
Cash Equivalents Short Term Investments And Interest recivable
Cash equivalents short term investments and interest recivable
Series A1 Preferred Units.
Series A1 Preferred Units [Member]
Series A1 Preferred Units
Asset Acquisition [Abstract]
Recently Adopted Accounting Pronouncements
Recently Adopted Accounting Pronouncements Policy [Text Block]
Recently adopted accounting pronouncements.
Summary of Outstanding Equity Instruments Excluded from Computation of Diluted Net Income (Loss) Per Share
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]
Debt Securities, Available-for-Sale [Table]
Entity Interactive Data Current
Entity Interactive Data Current
License and collaboration agreements.
License And Collaboration Agreements [Text Block]
License and Collaboration Agreements
Milestones [Domain]
Milestones [Domain]
Statement of Income Location, Balance [Domain]
Income Statement Location
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
Operating activities:
Genrix License Agreement [Member]
Genrix License Agreement [Member]
Genrix License Agreement
Entity Tax Identification Number
Entity Tax Identification Number
Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Stockholders' equity:
Stock price
Share Price
Share purchase price
Long-Term Debt, Type [Axis]
Long-term Debt, Type
License agreement obligations
License agreement obligations
License agreement obligations
Proceeds from Issuance or Sale of Equity
Proceeds from Issuance or Sale of Equity, Total
Proceeds from sale of equity
Local Phone Number
Local Phone Number
Related Party Transaction [Domain]
Related Party Transaction
Other current liabilities
Other Liabilities, Current
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Denominator
Gain on sale of Cullinan Pearl
Gain (Loss) On Sale Of Cullinan Pearl
Gain (Loss) On Sale Of Cullinan Pearl
Accounting Policies [Abstract]
Research and Development Expenses Axis
Research and Development Expenses Axis
Previously Reported [Member]
As Reported
Net Income (Loss) Attributable to Parent [Abstract]
Numerator:
Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table]
Income (Loss) Attributable to Noncontrolling Interest, before Tax
Net loss attributable to noncontrolling interests
2027
Lessee, Operating Lease, Liability, to be Paid, Year Four
Class of Stock [Domain]
Class of Stock
Commercial Paper [Member]
Commercial Paper
Cash, Cash Equivalents, and Short-Term Investments, Total
Cash, Cash Equivalents, and Short-Term Investments
Cash, cash equivalents, and short-term investments
Entity Emerging Growth Company
Entity Emerging Growth Company
Area of Land
Area of Land and Spaces