Debt Instrument, Principal Amount Issued, Percentage Of Face Value

No definition available.

Name:	cbre_DebtInstrumentPrincipalAmountIssuedPercentageOfFaceValue
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- Definition

Debt Instrument, Redemption Price, Discount Rate, Adjustment To Treasury Rate

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Redemption Price Following Change in Control, Percentage

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Line of Credit Facility, Maximum Borrowing Capacity Increase (Decrease)

+ References

No definition available.

+ Details

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Namespace Prefix:	cbre_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Long term debt percentage spread over daily interest rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	cbre_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Long term debt percentage spread over fixed interest rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	cbre_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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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_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the minimum ratio of earnings before interest, taxes, depreciation and amortization (EBITDA) to total interest expense required in the reporting entity's credit agreement.

+ References

No definition available.

+ Details

Name:	cbre_MinimumCoverageRatioOfEarningsBeforeInterestTaxDepreciationAndAmortizationToInterestExpenseExpressedInPercentage
Namespace Prefix:	cbre_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of long term debt outstanding that may be redeemed.

+ References

No definition available.

+ Details

Name:	cbre_PercentageOfLongTermDebtAvailableForRedemption
Namespace Prefix:	cbre_
Data Type:	dtr-types:percentItemType
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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Balance Type:	credit
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.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Long-Term Debt and Short-Term Borrowings - Long-Term Debt Narrative (Details)				12 Months Ended
	Aug. 05, 2022	Mar. 18, 2021 USD ($)	Aug. 13, 2015 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 EUR (€)	Dec. 31, 2021 USD ($)	Nov. 23, 2021 EUR (€)	Jul. 09, 2021 USD ($)	May 21, 2021 USD ($)	Dec. 31, 2020
Debt Instrument [Line Items]
Debt agreement term				10 years
2021 Credit Agreement
Debt Instrument [Line Items]
Minimum coverage ratio of EBITDA to total interest expense expressed in percentage				2.00%
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%
2.500% Senior Notes
Debt Instrument [Line Items]
Interest rate						2.50%				2.50%
2.500% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount		$ 500,000,000
Interest rate		2.50%		2.50%	2.50%
Percentage of face value		98.451%
Adjustment to treasury rate		0.20%
Debt issuance cost				$ 489,300,000		$ 488,100,000
2.500% Senior Notes \| Senior Notes \| Debt Instrument, Redemption, Period One [Member]
Debt Instrument [Line Items]
Redemption price percentage		100.00%
4.875% Senior Notes
Debt Instrument [Line Items]
Interest rate				4.875%	4.875%
4.875% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount			$ 600,000,000
Interest rate			4.875%
Redemption price percentage			99.24%
Percentage of notes available for redemption			100.00%
Redemption price percentage, following change in control			101.00%
Senior notes				$ 596,400,000		$ 595,500,000
Tranche A Term Loan Facility \| 2021 Credit Agreement \| Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount \| €							€ 300,000,000
Revolving credit facility \| 2019 Credit Agreement
Debt Instrument [Line Items]
Aggregate principal amount								$ 350,000,000
Revolving credit facility \| 2021 Credit Agreement
Debt Instrument [Line Items]
Debt agreement term	5 years
Amounts available to borrow under credit agreement									$ 3,150,000,000
Revolving credit facility \| 2021 Credit Agreement \| Minimum
Debt Instrument [Line Items]
Credit Agreement applicable fixed rate spread				0.68%
Credit Agreement applicable daily rate spread				0.00%
Revolving credit facility \| 2021 Credit Agreement \| Maximum
Debt Instrument [Line Items]
Credit Agreement applicable fixed rate spread				1.075%
Credit Agreement applicable daily rate spread				0.075%
Euro Term Loan Facility \| 2021 Credit Agreement
Debt Instrument [Line Items]
Aggregate principal amount \| €					€ 400,000,000
Borrowings outstanding				$ 427,800,000
Euro Term Loan Facility \| 2021 Credit Agreement \| Senior Notes \| Minimum \| EURIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (percent)				0.75%