v3.26.1
Borrowings - Schedule of Assets Held as Collateral Related to Secured Borrowings (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Jan. 31, 2026
Dec. 31, 2025
Debt Instrument [Line Items]      
Cash and cash equivalents $ 182.5   $ 180.5
Restricted cash 124.7   84.1
Mortgage servicing rights (MSRs), at fair value 3,025.9   2,825.3
Advances, net 431.1   483.4
Loans held for sale 3,150.2   1,891.7
Receivables, net ($254.9 and $64.2 related to VIEs) 365.0   189.8
REO ($97.7 and $81.0 related to VIEs) 101.0   83.8
Total Assets 17,735.2   16,170.6
Ginnie Mae Mortgage Servicing Rights Financing Facility | Secured Debt      
Debt Instrument [Line Items]      
Uncommitted available borrowing capacity   $ 450.0 $ 400.0
Asset Pledged as Collateral with Right | Ginnie Mae Mortgage Servicing Rights Financing Facility | Secured Debt      
Debt Instrument [Line Items]      
Proceeds from Lines of Credit 38.8    
Assets      
Debt Instrument [Line Items]      
Cash and cash equivalents 182.5    
Restricted cash 124.7    
Mortgage servicing rights (MSRs), at fair value 2,136.3    
Transferred MSRs, Including ESS 889.6    
Advances, net 431.1    
Loans held for sale 3,150.2    
Loans held for investment, at fair value 9,533.2    
Unsecuritized loans 63.3    
Receivables, net ($254.9 and $64.2 related to VIEs) 365.0    
REO ($97.7 and $81.0 related to VIEs) 101.0    
Total Assets 16,976.8    
Assets, Available Cash Held By Regulated Subsidiary Guarantors 145.3    
Pledged Assets      
Debt Instrument [Line Items]      
Cash and cash equivalents 0.0    
Restricted cash 66.0    
Mortgage servicing rights (MSRs), at fair value 2,141.2    
Transferred MSRs, Including ESS 889.6    
Advances, net 376.7    
Loans held for sale 3,099.8    
Loans held for investment, at fair value 9,533.2    
Unsecuritized loans 34.0    
Receivables, net ($254.9 and $64.2 related to VIEs) 260.0    
REO ($97.7 and $81.0 related to VIEs) 98.3    
Collateralized Debt Obligations [Member]      
Debt Instrument [Line Items]      
Cash and cash equivalents 0.0    
Restricted cash 0.0    
Mortgage servicing rights (MSRs), at fair value 1,313.4    
Transferred MSRs, Including ESS 813.4    
Advances, net 330.1    
Loans held for sale 3,167.2    
Loans held for investment, at fair value 9,437.4    
Unsecuritized loans 29.4    
Receivables, net ($254.9 and $64.2 related to VIEs) 273.0    
REO ($97.7 and $81.0 related to VIEs) 113.1    
Total Assets 15,477.1    
Senior Lien | Collateralized Debt Obligations [Member]      
Debt Instrument [Line Items]      
Transferred MSRs, ESS Financing Liabilities 18.8    
Senior Lien | Asset Pledged as Collateral with Right      
Debt Instrument [Line Items]      
Total Assets $ 16,498.9