New Accounting Pronouncements (Policies)	9 Months Ended
New Accounting Pronouncements (Policies)	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Readers of this Quarterly Report on Form 10-Q (Quarterly Report) should refer to the audited financial statements and notes to consolidated financial statements of CBRE Group, Inc., a Delaware corporation (which may be referred to in these financial statements as “CBRE,” “the company,” “we,” “us” and “our”), for the year ended December 31, 2023, which are included in our 2023 Annual Report on Form 10-K (2023 Annual Report), filed with the United States Securities and Exchange Commission (SEC) and also available on our website (www.cbre.com), since we have omitted from this Quarterly Report certain footnote disclosures which would substantially duplicate those contained in such audited financial statements. You should also refer to Note 2, Significant Accounting Policies, in the notes to consolidated financial statements in our 2023 Annual Report for further discussion of our significant accounting policies and estimates. Financial Statement Preparation The accompanying consolidated financial statements have been prepared in accordance with the rules applicable to quarterly reports on Form 10-Q and include all information and footnotes required for interim financial statement presentation, but do not include all disclosures required under accounting principles generally accepted in the United States (U.S.), or General Accepted Accounting Principles (GAAP), for annual financial statements.
Use of Estimates	Our consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S., which require management to make estimates and assumptions about future events. These estimates and the underlying assumptions affect the amounts reported in our consolidated financial statements and accompanying notes and are based on our best judgment. We evaluate our estimates and assumptions on an ongoing basis using historical experience and other factors, including consideration of the current economic environment, and adjust such estimates and assumptions when facts and circumstances dictate.
Recent Accounting Pronouncements Pending Adoption	Recent Accounting Pronouncements Pending Adoption In November 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” This update enhances reportable segment disclosures by requiring a public entity to: 1) disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker (CODM) and included within each reported measure of segment profit or loss, 2) disclose, on an annual and interim basis, an amount of other segment items by reportable segment and a description of its composition, 3) provide all annual disclosures about a reportable segment’s profit or loss and assets currently required by Topic 280 in interim periods, 4) disclose the title and position of the CODM and an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources, and 5) provide all the disclosures required by this update and all existing segment disclosures in Topic 280 if the entity has a single reportable segment. This ASU also clarifies that, in addition to the measure that is most consistent with the measurement principles under GAAP, a public entity is not precluded from reporting additional measures of a segment’s profit or loss that are used by the CODM in assessing segment performance and deciding how to allocate resources. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We are evaluating the impact this guidance will have on our consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, “Improvements to Income Tax Disclosures.” This ASU requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid and will be effective for annual periods beginning after December 15, 2024. The new requirements should be applied on a prospective basis with an option to apply them retrospectively. Early adoption is permitted. We are evaluating the impact that ASU 2023-09 will have on our consolidated financial statements and related disclosures.