v3.25.2
Fair Value - Summary of Changes in Fair Value Included in Current Period Results of Operations (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Credit Risk Transfer Strips at Fair Value [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     $ 13,426  
Credit Risk Transfer Strips at Fair Value [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     13,426  
Credit Risk Transfer Strips at Fair Value [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Credit Risk Transfer Strips at Fair Value [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Credit Risk Transfer Strips at Fair Value [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Credit Risk Transfer Strips [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) $ 15,474 $ 12,071   $ 53,096
Credit Risk Transfer Strips [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 15,474 12,071   53,096
Credit Risk Transfer Strips [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Credit Risk Transfer Strips [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Credit Risk Transfer Strips [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Mortgage-backed securities [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)   (28,339)   (63,446)
Mortgage-backed securities [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)   (34,925)   (73,123)
Mortgage-backed securities [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Mortgage-backed securities [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Mortgage-backed securities [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)   6,586   9,677
Interest-only security payable [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (599) (481) (2,331) (41)
Interest-only security payable [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (599) (481) (2,331) (41)
Interest-only security payable [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Interest-only security payable [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Interest-only security payable [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Asset-Backed Financings of VIEs [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (14,288) 691 (42,343) 8,659
Asset-Backed Financings of VIEs [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (14,793) 1,295 (44,216) 8,771
Asset-Backed Financings of VIEs [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Asset-Backed Financings of VIEs [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Asset-Backed Financings of VIEs [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 505 (604) 1,873 (112)
Liabilities, Total [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 6,743 210 (44,674) 8,618
Liabilities, Total [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 43,697 814 (46,547) 8,730
Liabilities, Total [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 34,080 0
Liabilities, Total [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (75,128) 0
Liabilities, Total [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 4,094 (604) 1,873 (112)
Mortgage-backed securities at fair value [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     79,419  
Mortgage-backed securities at fair value [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Mortgage-backed securities at fair value [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Mortgage-backed securities at fair value [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     17,652  
Mortgage-backed securities at fair value [Member] | Mortgage-backed securities [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 22,146      
Mortgage-backed securities at fair value [Member] | Mortgage-backed securities [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 14,564      
Mortgage-backed securities at fair value [Member] | Mortgage-backed securities [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 7,582      
Loans acquired for sale at fair value [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Loans acquired for sale at fair value [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     80,591  
Loans acquired for sale at fair value [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Loans acquired for sale at fair value [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Loans acquired for sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 34,080 1,969 80,591 1,632
Loans acquired for sale [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Loans acquired for sale [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 34,080 1,969   1,632
Loans acquired for sale [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Loans acquired for sale [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
At fair value [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     97,071  
Loans held for investment [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 10,171 (3,347) 38,165 (6,760)
Loans held for investment [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 13,659 (2,742) 42,340 (4,020)
Loans held for investment [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Loans held for investment [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 0
Loans held for investment [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (3,488) (605) (4,175) (2,740)
MSRs at fair value [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
MSRs at fair value [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
MSRs at fair value [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     (219,718)  
MSRs at fair value [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense)     0  
Mortgage servicing rights [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (75,128) (50,556) (219,718) (78,758)
Mortgage servicing rights [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Mortgage servicing rights [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Mortgage servicing rights [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (75,128) (50,556)   (78,758)
Mortgage servicing rights [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0  
Assets, Total [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (14,887) (68,202) 9,535 (94,236)
Assets, Total [Member] | Net Gains (Losses) on Investments and Financings [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (15,392) (25,596) 135,185 (24,047)
Assets, Total [Member] | Net Gains on Loans Acquired for Sale [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) (0) 1,969 80,591 1,632
Assets, Total [Member] | Net Loan Servicing Fees [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) 0 (50,556) (219,718) (78,758)
Assets, Total [Member] | Net Interest Expense [Member]        
Fair Value, Option, Quantitative Disclosures [Line Items]        
Changes in fair value included in current period income (expense) $ 505 $ 5,981 $ 13,477 $ 6,937