v3.25.4

Investments in Unconsolidated Subsidiaries - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Estimated fair value of investment		$ 9
Asset impairments			$ 0
Revenue	$ 40,550	35,767	31,949
Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Estimated fair value of investment	57
Real Estate Investment
Schedule of Equity Method Investments [Line Items]
Estimated fair value of investment	42
Investment management \| Related party \| Real estate investments
Schedule of Equity Method Investments [Line Items]
Revenue	274	333	279
Related party receivable	91	156
Development and construction management revenues \| Related party
Schedule of Equity Method Investments [Line Items]
Revenue	98	114	$ 165
Related party receivable	$ 14	$ 19
Ownership percentage \| Minimum
Schedule of Equity Method Investments [Line Items]
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage	1.00%
Ownership percentage \| Maximum
Schedule of Equity Method Investments [Line Items]
Equity method investments in unconsolidated subsidiaries, variations in ownership percentage	50.00%

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CBRE GROUP, INC. 10-K