Commitments and Contingencies (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Funded loans unpaid principal	$ 35,600.0
Letters of credit outstanding	142.0
Accrued loan loss	62.4	$ 57.1
Assets available for recourse	1,100.0
Guarantees total	$ 49.2
Co-investments typically range	2.00%
Commitments to investment in future real estate investment	$ 154.2
Commitments to investment in unconsolidated real estate subsidiary	45.9
Commitment to purchase additional shares	70.0
Maximum
Loss Contingencies [Line Items]
Commitment to purchase additional shares	150.0
Forbearance Of Loans, CARES Act
Loss Contingencies [Line Items]
Advances for principal and interest	9.3
Warehouse Receivable
Loss Contingencies [Line Items]
Warehouse receivables	633.6
Funded loans subject to loss sharing arrangements
Loss Contingencies [Line Items]
Funded loans unpaid principal	31,400.0
Funded loans not subject to loss sharing arrangements
Loss Contingencies [Line Items]
Letters of credit outstanding	95.0	95.0
SBL Program
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 5.0	$ 5.0
Percentage of maximum original principal amount loan loss	10.00%
CBRE Capital Markets
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 95.0

Advances for principal and interest

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- Definition

Assets available for recourse under the Fannie Mae DUS lender program.

+ References

No definition available.

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- Definition

The reporting entity's aggregate commitments to fund future co-investments with its clients in certain real estate investments.

+ References

No definition available.

+ Details

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- Definition

The reporting entity's aggregate commitments to fund additional capital to certain unconsolidated real estate subsidiaries.

+ References

No definition available.

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- Definition

Principal amount outstanding as of the balance-sheet date of loans funded as part of a loss sharing arrangement with a third party.

+ References

No definition available.

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Maximum potential amount of future payments (undiscounted) the reporting entity could be required to make excluding (1) those for which the reporting entity has an outstanding liability already accrued on its consolidated statement of financial position and (2) completion and budget guarantees relating to the reporting entity's Development Services segment.

+ References

No definition available.

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The reporting entity's estimate of loss sharing reserves on loans originated that are subject to a loss sharing arrangement with a third party.

+ References

No definition available.

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- Definition

Percentage of equity in real estate investment.

+ References

No definition available.

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Maximum original principal amount loan loss percentage.

+ References

No definition available.

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Purchase Commitments For Additional Sponsorship Company Shares

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- 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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Amount, before allowance for credit loss, of financing receivable.

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