Subsequent Events	9 Months Ended
Sep. 30, 2026
Subsequent Events [Abstract]
Subsequent Events	18. Subsequent Events On October 20, 2026, CBRE announced a definitive agreement to acquire Onnec Group Limited (Onnec), a leading provider of data center infrastructure services across Europe and Asia Pacific. The initial purchase price is £460 million (approximately $610 million) in cash plus a potential earnout of up to £300 million (approximately $400 million), subject to Onnec achieving certain growth thresholds. Following the completion of the acquisition, Onnec will operate as part of CBRE's Critical Infrastructure Services line of business within the BOE segment.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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