Commitments and Contingencies (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Funded loans unpaid principal	$ 41,100.0
Letters of credit outstanding	236.4
Accrued loan loss	68.1	$ 65.1
Assets available for recourse	981.8
Guarantees total	198.4
Commitments to investment in future real estate investment	$ 116.9
Maximum Future Commitments Equity In Real Estate Investment, Percent	2.00%
Commitments to investment in future real estate investment	0.50
Commitment to investment in consolidated projects	$ 200.7
Commitments to investment in unconsolidated real estate subsidiary	95.5
Warehouse Receivable
Loss Contingencies [Line Items]
Warehouse receivables	529.2
Funded Loan Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Funded loans unpaid principal	37,500.0
Letters of credit outstanding	140.0	113.0
SBL Program
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 5.0	$ 5.0
Percentage of maximum original principal amount loan loss	10.00%
Funded Loan Not Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 145.0

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

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

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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.

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Maximum original principal amount loan loss percentage.

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

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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