Description of Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2026
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation. The accompanying unaudited interim consolidated financial statements ("Consolidated Financial Statements") have been prepared in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP") and the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim financial statements. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the SEC rules and regulations. These Consolidated Financial Statements should be read in conjunction with the audited consolidated financial statements and the notes thereto for the year ended December 31, 2025, which are included in the Company's Annual Report on Form 10-K as filed with the SEC on February 26, 2026 (the "December 31, 2025 Consolidated Financial Statements"). The significant accounting policies used in preparing these Consolidated Financial Statements were applied on a basis consistent with those reflected in the December 31, 2025 Consolidated Financial Statements. In the opinion of management, the Consolidated Financial Statements contain all adjustments (consisting of a normal, recurring nature) necessary to present fairly the Company's financial position, results of operations, cash flows and changes in stockholders' equity as of the dates and for the periods indicated. The unaudited results of operations for the three months ended March 31, 2026 are not necessarily indicative of results that may be expected for the year ending December 31, 2026.
Use of Estimates	Use of Estimates. The preparation of the accompanying Consolidated Financial Statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect amounts reported in the Consolidated Financial Statements and accompanying disclosures. Although these estimates are based on management’s best knowledge of current events and actions that the Company may undertake in the future, actual results may differ from those estimates.
Reclassifications	Reclassifications. Certain prior period balances have been reclassified to conform to the current period presentation. These reclassifications were not material to the previously reported Consolidated Financial Statements.
Principles of Consolidation	Principles of Consolidation. The accompanying Consolidated Financial Statements include the accounts of the Company and its 100% owned subsidiaries, including DealerClub since the date of acquisition. All intercompany transactions and accounts have been eliminated in consolidation.
Recently Issued Accounting Standards Not Yet Adopted	Recently Issued Accounting Standards Not Yet Adopted. In December 2025, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements, which clarifies current interim disclosure requirements and provides a comprehensive list of required interim disclosures. The update also establishes a principle under which a company must disclose events since the end of the last annual reporting period that have a material impact on the company. Per the FASB, the amendment is not intended to change the fundamental nature of interim reporting or expand or reduce current interim disclosure requirements but rather provide clarity and improve navigability of the existing interim reporting requirements. This amendment is effective for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted and entities are permitted to apply the new updates either prospectively or retrospectively to any or all periods presented in the financial statements. The Company is currently evaluating this new guidance and its impact on its Consolidated Financial Statements and related disclosures. In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other-Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which modernizes the accounting for internal-use software costs by eliminating the stage-based model in current U.S. GAAP and clarifying when capitalization of software development costs are appropriate. The standard removes the concept of discrete development stages and introduces a principle-based framework centered on whether management has authorized and committed to funding the project, and whether it is probable that the project will be completed and the software will be used to perform its intended function. This amendment is effective for annual reporting periods beginning after December 15, 2027, and for interim reporting periods beginning after December 15, 2027. Early adoption is permitted and entities are permitted to apply the new guidance in a prospective, modified or retrospective approach. The Company is currently evaluating this new guidance and its impact on its Consolidated Financial Statements and related disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement Reporting Comprehensive Income Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which requires companies to provide more detailed and organized disclosures of their expenses in their income statements. The standard requires breaking down expenses into specific categories, such as employee compensation and costs related to depreciation and amortization. This amendment is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, on a prospective basis and early adoption and retrospective application is permitted. The Company is currently evaluating this new guidance and its impact on its financial statement disclosures.

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
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-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: 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

+ Details

Cars.com Inc. 10-Q