Transactions with Related Parties - Summary of Management Fee Expense (Detail) - PNMAC Capital Management LLC [Member] - USD ($) $ in Thousands |
3 Months Ended | |
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Mar. 31, 2026 |
Mar. 31, 2025 |
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| Related Party Transaction [Line Items] | ||
| Total management fee incurred during the period | $ 6,762 | $ 7,012 |
| Average shareholders' equity amounts used to calculate base management fee expense | 1,828,237 | 1,895,785 |
| Base management fee [Member] | ||
| Related Party Transaction [Line Items] | ||
| Total management fee incurred during the period | 6,762 | 7,012 |
| Performance incentive fee [Member] | ||
| Related Party Transaction [Line Items] | ||
| Total management fee incurred during the period | $ 0 | $ 0 |
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- Definition Average shareholders' equity amounts used to calculate management fee expense. No definition available.
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- Definition Amount of expense for investment management fee, including, but not limited to, expense in connection with research, selection, supervision, and custody of investment. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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