Maximum leverage ratio during first four quarter that qualified acquisition is consummated.

No definition available.

Name:	cbre_MaximumLeverageRatioDuringFirstFourQuarterThatQualifiedAcquisitionIsConsummated
Namespace Prefix:	cbre_
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Balance Type:	na
Period Type:	duration

- Definition

This element represents the maximum ratio of debt less available cash to earnings before interest, taxes, depreciation and amortization (EBITDA) allowed in the reporting entity's credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	cbre_
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Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

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- Definition

Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Fair value of the amount outstanding under the credit facility.

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Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Long-Term Debt and Short-Term Borrowings - Revolving Credit Facility Narrative (Details) - USD ($) $ in Millions	Jun. 23, 2026	Jun. 24, 2025	Dec. 02, 2024	Jun. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Letters of credit outstanding amount				$ 344
Revolving credit agreements \| Senior notes
Debt Instrument [Line Items]
Maximum leverage ratio of total debt less available cash to EBITDA expressed in percentage		4.25%
Maximum leverage ratio during first four quarter that qualified acquisition is consummated		4.75%
New 364-Day Revolving credit agreement \| Senior notes
Debt Instrument [Line Items]
Maximum leverage ratio of total debt less available cash to EBITDA expressed in percentage	4.25%
Maximum leverage ratio during first four quarter that qualified acquisition is consummated	4.75%
Revolving credit facility \| Revolving credit agreements
Debt Instrument [Line Items]
Debt agreement term		5 years	5 years
Amounts available to borrow under credit agreement		$ 3,500
Line of credit facility outstanding					$ 0
Revolving credit facility \| Revolving credit agreements \| Line of credit
Debt Instrument [Line Items]
Letters of credit outstanding amount		300
Revolving credit facility \| Revolving credit agreements \| Swingline loans
Debt Instrument [Line Items]
Letters of credit outstanding amount		$ 300
Revolving credit facility \| Revolving credit agreements \| Secured overnight financing rate (SOFR) overnight index swap
Debt Instrument [Line Items]
Variable rate (as a percent)		1.00%
Revolving credit facility \| Revolving credit agreements \| Secured overnight financing rate (SOFR) overnight index swap \| Minimum
Debt Instrument [Line Items]
Variable rate (as a percent)		0.63%
Revolving credit facility \| Revolving credit agreements \| Secured overnight financing rate (SOFR) overnight index swap \| Maximum
Debt Instrument [Line Items]
Variable rate (as a percent)		1.10%
Revolving credit facility \| Revolving credit agreements \| Base rate \| Minimum
Debt Instrument [Line Items]
Variable rate (as a percent)		0.00%
Revolving credit facility \| Revolving credit agreements \| Base rate \| Maximum
Debt Instrument [Line Items]
Variable rate (as a percent)		0.10%
Revolving credit facility \| Revolving credit agreements \| Fed funds effective rate overnight index swap rate
Debt Instrument [Line Items]
Variable rate (as a percent)		0.50%
Revolving credit facility \| 2019 Credit agreement
Debt Instrument [Line Items]
Line of credit facility outstanding				0	0
Revolving credit facility \| 2019 Credit agreement \| Line of credit
Debt Instrument [Line Items]
Letters of credit outstanding amount				24	$ 17
Revolving credit facility \| New 364-Day Revolving credit agreement
Debt Instrument [Line Items]
Debt agreement term	364 days
Amounts available to borrow under credit agreement	$ 1,000
Line of credit facility outstanding				$ 0
Revolving credit facility \| New 364-Day Revolving credit agreement \| Secured overnight financing rate (SOFR) overnight index swap
Debt Instrument [Line Items]
Variable rate (as a percent)	1.00%
Revolving credit facility \| New 364-Day Revolving credit agreement \| Secured overnight financing rate (SOFR) overnight index swap \| Minimum
Debt Instrument [Line Items]
Variable rate (as a percent)	0.645%
Revolving credit facility \| New 364-Day Revolving credit agreement \| Secured overnight financing rate (SOFR) overnight index swap \| Maximum
Debt Instrument [Line Items]
Variable rate (as a percent)	1.125%
Revolving credit facility \| New 364-Day Revolving credit agreement \| Base rate \| Minimum
Debt Instrument [Line Items]
Variable rate (as a percent)	0.00%
Revolving credit facility \| New 364-Day Revolving credit agreement \| Base rate \| Maximum
Debt Instrument [Line Items]
Variable rate (as a percent)	0.10%
Revolving credit facility \| New 364-Day Revolving credit agreement \| Fed funds effective rate overnight index swap rate
Debt Instrument [Line Items]
Variable rate (as a percent)	0.50%