v3.26.3
Long-Term Debt - Schedule of Contractual Maturities on Long Term Debt Obligations (Detail) - USD ($)
$ in Thousands
Sep. 30, 2032
Sep. 30, 2031
Sep. 30, 2030
Sep. 30, 2029
Sep. 30, 2028
Sep. 30, 2027
Sep. 30, 2026
Dec. 31, 2025
Debt Instrument [Line Items]                
Notes payable secured by credit risk transfer and mortgage servicing assets $ 0 $ 0 $ 0 $ 0 $ 1,286,964 $ 1,221,333 $ 2,508,297  
Unsecured senior notes             697,500 $ 1,042,500
Interest-only security payable at fair value 34,608 0 0 0 0 0 34,608 37,650
Asset-backed financings at fair value 13,625,245 0 0 0 0 0 13,625,245  
Exchangeable Senior Notes [Member]                
Debt Instrument [Line Items]                
Unsecured senior notes 0 0 277,500 366,500 53,500 0 366,500 $ 711,500
Total $ 13,659,853 $ 0 $ 277,500 $ 366,500 $ 1,340,464 $ 1,221,333 $ 16,865,650