| Line Item | Jun 30, 2026 | Mar 31, 2026 | Dec 31, 2025 | Sep 30, 2025 | Jun 30, 2025 | Mar 31, 2025 | Dec 31, 2024 | Sep 30, 2024 | Jun 30, 2024 | Mar 31, 2024 | Dec 31, 2023 | Sep 30, 2023 | Jun 30, 2023 | Mar 31, 2023 | Dec 31, 2022 | Sep 30, 2022 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Net interest expense: | ||||||||||||||||
| Interest income | ||||||||||||||||
| Interest expense | ||||||||||||||||
| Net interest expense | ||||||||||||||||
| Net servicing income: | ||||||||||||||||
| Servicing income | ||||||||||||||||
| Servicing costs | ||||||||||||||||
| Net servicing income | ||||||||||||||||
| Other income (loss): | ||||||||||||||||
| Loss on investment securities | ||||||||||||||||
| Loss on servicing asset | ||||||||||||||||
| Gain (loss) on derivative instruments | — | — | ||||||||||||||
| Gain on mortgage loans held-for-sale | ||||||||||||||||
| Other income | ||||||||||||||||
| Total other loss | ||||||||||||||||
| Expenses: | ||||||||||||||||
| Compensation and benefits | ||||||||||||||||
| Other operating expenses | ||||||||||||||||
| Loss contingency accrual | — | — | — | |||||||||||||
| Total expenses | ||||||||||||||||
| Income (loss) before income taxes | ||||||||||||||||
| Provision for income taxes | ||||||||||||||||
| Net income (loss) | ||||||||||||||||
| Dividends on preferred stock | ||||||||||||||||
| Net income (loss) attributable to common stockholders | ||||||||||||||||
| Basic earnings (loss) per weighted average common share (in usd per share) | — | |||||||||||||||
| Diluted earnings (loss) per weighted average common share (in usd per share) | — |