Credit Spread Adjustment Rate

No definition available.

Name:	cbre_CreditSpreadAdjustmentRate
Namespace Prefix:	cbre_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

Name:	cbre_LineOfCreditFacilityAccordionFeatureIncreaseLimit
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

Name:	cbre_LongTermDebtPercentageSpreadOverDailyInterestRate
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

Name:	cbre_LongTermDebtPercentageSpreadOverFixedInterestRate
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

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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current portion 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cbre_TwoThousandTwentyOneCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=cbre_CanadianAustralianAndNewZealandSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=cbre_UnitedKingdomSubsidiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cbre_RevolvingCreditFacilityMaturityDateAugust52027Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cbre_RevolvingCreditFacilityMaturityDateMarch312027Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=cbre_TurnerTownsendHoldingsLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=cbre_RevolvingCreditFacilityMaturityDateNovember112022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=cbre_SONIAOvernightRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Long-Term Debt and Short-Term Borrowings - Revolving Credit Facility Narrative (Details) € in Millions		3 Months Ended
	Aug. 05, 2022 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2023 EUR (€)	Dec. 31, 2022 USD ($)	Mar. 31, 2022 EUR (€)	Jan. 01, 2022	May 21, 2021 USD ($)
Debt Instrument [Line Items]
Revolving credit facility		$ 1,209,000,000		$ 178,000,000
Revolving credit facility \| 2021 Credit Agreement
Debt Instrument [Line Items]
Amounts available to borrow under credit agreement							$ 3,150,000,000
Credit spread adjustment rate						0.0326%
Debt agreement term	5 years
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%
Revolving credit facility \| 2021 Credit Agreement \| Canadian, Australian and New Zealand subsidiaries
Debt Instrument [Line Items]
Amounts available to borrow under credit agreement		$ 200,000,000
Revolving credit facility \| 2021 Credit Agreement \| U.K. subsidiaries
Debt Instrument [Line Items]
Amounts available to borrow under credit agreement		320,000,000
Revolving credit facility \| Revolving Credit Agreement
Debt Instrument [Line Items]
Amounts available to borrow under credit agreement	$ 3,500,000,000
Debt agreement term	5 years
Revolving credit facility \| Revolving Credit Agreement \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Revolving credit facility \| 2027 Credit Agreement \| Turner & Townsend
Debt Instrument [Line Items]
Amounts available to borrow under credit agreement \| €			€ 120.0
Additional accordion option \| €					€ 20.0
Revolving credit facility		$ 8,600,000	€ 7.0
Revolving credit facility \| Revolving Credit Facility, Maturity Date November 11, 2022 \| Turner & Townsend \| SONIA
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.75%