Servicing Revenue - Schedule of Product (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Concentration Risk [Line Items]
UPB	$ 58,130	$ 47,846
Effective Earnings Rate	0.04%	0.07%
Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	100.00%	100.00%
Fannie Mae
Concentration Risk [Line Items]
UPB	$ 7,937	$ 7,860
Effective Earnings Rate	0.10%	0.21%
Fannie Mae \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	14.00%	16.00%
Ginnie Mae
Concentration Risk [Line Items]
UPB	$ 5,205	$ 5,125
Effective Earnings Rate	0.08%	0.17%
Ginnie Mae \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	9.00%	11.00%
Freddie Mac
Concentration Risk [Line Items]
UPB	$ 8,877	$ 8,649
Effective Earnings Rate	0.03%	0.08%
Freddie Mac \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	15.00%	18.00%
Bridge
Concentration Risk [Line Items]
UPB	$ 422	$ 836
Effective Earnings Rate	0.02%	0.08%
Bridge \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	1.00%	2.00%
Affordable
Concentration Risk [Line Items]
UPB	$ 448	$ 425
Effective Earnings Rate	0.03%	0.13%
Affordable \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	1.00%	1.00%
Benefit Street Partners
Concentration Risk [Line Items]
UPB	$ 10,025	$ 0
Effective Earnings Rate	0.03%	0.00%
Servicing asset at fair value, amount	$ 4,900
Benefit Street Partners \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	17.00%	0.00%
Private Label
Concentration Risk [Line Items]
UPB	$ 25,216	$ 24,951
Effective Earnings Rate	0.01%	0.02%
Private Label \| Revenue, Product and Service Benchmark \| Product Concentration Risk
Concentration Risk [Line Items]
Percentage	43.00%	52.00%

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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