Name:	cbg_LineOfCreditLondonInterBankOfferRateFloor
Namespace Prefix:	cbg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The amount of line of credit capacity that has matured and is no longer available to the reporting entity.

No definition available.

Name:	cbg_LineOfCreditMatured
Namespace Prefix:	cbg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The change in account balance on warehouse line of credit during the period related to non-cash activity.

No definition available.

Name:	cbg_NonCashActivityBasedIncreaseDecreaseInWarehouseLinesOfCredit
Namespace Prefix:	cbg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The change in account balance on warehouse receivables during the period related to non-cash activity.

No definition available.

Name:	cbg_NonCashActivityBasedIncreaseDecreaseInWarehouseReceivables
Namespace Prefix:	cbg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Date the credit facility terminates, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

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.

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

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Name:	us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroupMortgage
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

No definition available.

Name:	us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=cbg_TdBankSecuredCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_CreditFacilityAxis=cbg_InterestAtDailyOneMonthLiborPlusOnePointThreeFivePercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_WarehouseAgreementBorrowingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=cbg_LineOfCreditFacilityMatureDateOctoberTwentyThreeTwoThousandSeventeenMember
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Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_DebtInstrumentAxis=cbg_InterestAtDailyOneMonthLiborPlusTwoPointZeroZeroPercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=cbg_LineOfCreditFacilityMatureDateJanuaryThirtyTwoThousandAndSeventeenMember
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Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=cbg_LineOfCreditFacilityMatureDateMayTwentyFiveThousandSeventeenMember
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Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_CounterpartyNameAxis=cbg_AsSoonAsPooledSaleAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

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

Name:	us-gaap_DebtInstrumentAxis=cbg_LineOfCreditFacilityMaturityDateJulyTwentySevenTwoThousandSeventeenMember
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