Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Loss Contingencies [Line Items]
Funded loans unpaid principal	$ 42,900.0	$ 42,900.0
Letters of credit outstanding	254.7	254.7
Accrued loan loss	60.4	60.4	$ 67.4
Assets available for recourse	2,100.0	2,100.0
Guarantees total	196.5	196.5
Recognized revenue included in contract liability	57.8	189.7
Contingent deferred consideration		(271.3)	(266.1)
Reserves for sales and use taxes	24.2	$ 24.2	3.2
Maximum future commitments equity in real estate investment, percent		2.00%
Commitments to investment in future real estate investment	157.9	$ 157.9
Commitments to investment in future real estate investment		0.50
Commitment to investment in consolidated projects	168.0	$ 168.0
Commitments to investment in unconsolidated real estate subsidiary	68.7	68.7
Performance Guarantee
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	988.5	988.5	241.8
Other Current Liabilities
Loss Contingencies [Line Items]
Recognized revenue included in contract liability		(267.6)	(264.1)
Warehouse Receivable
Loss Contingencies [Line Items]
Warehouse receivables	505.7	505.7
Funded Loan Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Funded loans unpaid principal	39,500.0	39,500.0
Letters of credit outstanding	150.0	150.0	140.0
SBL Program
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 5.0	$ 5.0	$ 5.0
Percentage of maximum original principal amount loan loss	10.00%	10.00%
Funded Loan Not Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 155.0	$ 155.0

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

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