v3.26.1
Relationship with BLG and Bayview Financial (Detail) - USD ($)
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Schedule of Equity Method Investments [Line Items]      
Revenue from contract with customer $ 418,000,000 $ 397,000,000  
Deposits 163,741,000,000   $ 166,909,000,000
Bayview Financial      
Schedule of Equity Method Investments [Line Items]      
Deposits $ 3,600,000,000   3,500,000,000
Bayview Lending Group      
Schedule of Equity Method Investments [Line Items]      
Ownership percentage (as a percent) 20.00%    
Equity method investments $ 0    
Bayview Lending Group | Other Revenues From Operations      
Schedule of Equity Method Investments [Line Items]      
Income from equity method investments 33,000,000    
Bayview Lending Group and Bayview Financial      
Schedule of Equity Method Investments [Line Items]      
Outstanding principal balances of mortgage servicing rights 847,000,000   875,000,000
Bayview Financial      
Schedule of Equity Method Investments [Line Items]      
Outstanding principal balances of residential mortgage loans from Bayview Financial 124,000,000,000.0   156,900,000,000
Revenues from sub-servicing 63,000,000 $ 41,000,000  
Investment securities in held-to-maturity portfolio securitized by Bayview Financial 30,000,000   32,000,000
Commitments to extend credit 956,000,000    
Outstanding balance $ 802,000,000   $ 635,000,000