Commitments and Contingencies (Details) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Loss Contingencies [Line Items]
Funded loans unpaid principal	$ 46,600
Letters of credit outstanding	286
Accrued loan loss	63	$ 63
Assets available for recourse	2,300
Guarantees total	193
Recognized revenue included in contract liability	(100)
Deferred and contingent consideration	(109)	(93)
Indirect tax liability	93	91
Commitments to investment in future real estate investment	$ 183
Commitments to investment in future real estate investment	0.50
Commitment to investment in consolidated projects	$ 345
Commitments to investment in unconsolidated real estate subsidiary	54
Accounts Payable, Accrued Expenses and Long-term Deferred and Contingent Consideration
Loss Contingencies [Line Items]
Recognized revenue included in contract liability	(204)	199
Performance Guarantee
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	798	808
Warehouse Receivable
Loss Contingencies [Line Items]
Warehouse receivables	696
Funded Loan Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Funded loans unpaid principal	43,200
Letters of credit outstanding	165	160
SBL Program
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 5	$ 5
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	$ 170

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

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