Mortgage Loan Participation Purchase and Sale Agreement - Summary of Mortgage Loan Participation Purchase and Sale Agreement (Detail) - Mortgage Loan Participation Purchase and Sale Agreement [Member] - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Mortgage Loan Participation Purchase And Sale Agreement [Line Items] | ||||
| Average balance | $ 0 | $ 1,612 | $ 0 | $ 6,618 |
| Weighted average interest rate | 0.00% | 5.93% | 0.00% | 5.69% |
| Total interest expense | $ 31 | $ 55 | $ 94 | $ 375 |
| Maximum daily amount outstanding | $ 0 | $ 11,371 | $ 0 | $ 49,266 |