Commitments and Contingencies (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Loss Contingencies [Line Items]
Funded loans unpaid principal	$ 46,800	$ 46,800
Letters of credit outstanding	292	292
Accrued loan loss	64	64	$ 63
Assets available for recourse	820	820
Guarantees total	180	180
Recognized revenue included in contract liability	(48)	(148)
Contingent deferred consideration		110	93
Indirect tax liabilities primarily related to sales and use tax	96	96	91
Commitments to investment in future real estate investment	183	$ 183
Commitments to investment in future real estate investment (as a percent)		0.50
Commitment to investment in consolidated projects	328	$ 328
Commitments to investment in unconsolidated real estate subsidiary	54	54
Accounts Payable, Accrued Expenses and Long-term Deferred and Contingent Consideration
Loss Contingencies [Line Items]
Recognized revenue included in contract liability		(221)	199
Performance Guarantee
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	904	904	808
Warehouse Receivable
Loss Contingencies [Line Items]
Warehouse receivables	255	255
Funded Loan Subject to Loss Sharing Arrangements
Loss Contingencies [Line Items]
Funded loans unpaid principal	43,500	43,500
Letters of credit outstanding	165	165	160
SBL Program
Loss Contingencies [Line Items]
Letters of credit outstanding	$ 5	$ 5	$ 5
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	$ 170	$ 170

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