Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2025
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting.
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The condensed results of operations for this interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC.
Use of Estimates	Use of Estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.
Significant Accounting Policies	Significant Accounting Policies There have been no material changes to our significant accounting policies this interim period, as compared to the significant accounting policies disclosed in “Note 2. Basis of Presentation and Summary of Significant Accounting Policies” of the “Notes to Financial Statements” included in Part II, Item 8 of our 2024 Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC.
Recently Issued Accounting Standards Not Yet Adopted	Recently Issued Accounting Standards Not Yet Adopted In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounts Standards Update (“ASU”) 2024-03, Disaggregation of Income Statement Expenses ("ASU 2024-03"), which enhances transparency in income statement disclosures. ASU 2024-03 requires entities to disclose detailed information about specific components of income statement expenses, such as employee compensation, depreciation, and amortization, as well as other significant expense categories. The objective is to provide financial statement users with greater insight into the nature and variability of expenses, improving their ability to analyze financial performance and make informed decisions. ASU 2025-01 clarified that this ASU 2024-03 is effective for the annual reporting periods beginning after December 15, 2026 and for interim periods within annual reporting periods beginning after December 15, 2027 with early adoption permitted. The Company expects to adopt this ASU during the year ended December 31, 2027 on a prospective basis and is currently evaluating the impact on its financial statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures ("ASU 2023-09"), which enhances transparency in income tax disclosures. ASU 2023-09 requires entities to disclose (1) specific categories in the rate reconciliation, (2) the income or loss from continuing operations before income tax expense or benefit (separated between domestic and foreign) and (3) income tax expense or benefit from continuing operations (separated by federal, state and foreign). ASU 2023-09 also requires entities to disclose their income tax payments to international, federal, state and local jurisdictions, among other changes. The Company will adopt this ASU as of December 31, 2025 on a prospective basis and is currently evaluating the impact on its financial statements.

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-12

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-9

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 275
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-Section 55
-Paragraph 6
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-URI https://asc.fasb.org/1943274/2147482836/275-10-55-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-4

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

+ Details

CytomX Therapeutics, Inc. 10-Q