v3.25.4

N-2 - $ / shares | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2020
Cover [Abstract] |  |  |  |  |  |
Entity Central Index Key | 0001383414 |  |  |  |  |
Amendment Flag | true |  |  |  |  |
Amendment Description | PennantPark Investment Corporation, a Maryland corporation, or together with its subsidiaries, where applicable, or the Company, which may also be referred to as “we,” “us” or “our,” is filing this Amendment No. 1, or this Amendment, to our Annual Report on Form 10-K for the fiscal year ended September 30, 2025, or the Form 10-K, which was initially filed with the Securities and Exchange Commission, or the SEC, on November 24, 2025. We are filing this Amendment to clarify that the financial information disclosed in Note 13 for JF Intermediate, LLC and AKW Holdings Limited was audited as part of RSM US LLP’s audit of the consolidated statements of assets and liabilities of the Company and its subsidiaries, including the consolidated schedules of investments, as of September 30, 2025 and 2024, and the related consolidated statements of operations, changes in net assets and cash flows for each of the three years in the period ended September 30, 2025, and the related notes to the consolidated financial statements. This Amendment also includes the filing of new Exhibits 31.1, 31.2, 32.1 and 32.2, certifications of our Chief Executive Officer and Chief Financial Officer, pursuant to Rule 13a-14(a) and (b) of the Securities Exchange Act of 1934, as amended. Except as described above, no other changes have been made to the Form 10-K. This Amendment does not reflect subsequent events that may have occurred after the original filing date of the Form 10-K or modify or update in any way disclosures made in the Form 10-K, except as required to reflect the revisions discussed above. Among other things, forward-looking statements made in the Form 10-K have not been revised to reflect events that occurred or facts that became known to us after filing of the Form 10-K, and such forward-looking statements should be read in their historical context. Furthermore, this Amendment should be read in conjunction with the Form 10-K and with our subsequent filings with the SEC. |  |  |  |  |
Securities Act File Number | 814-00736 |  |  |  |  |
Document Type | 10-K/A |  |  |  |  |
Entity Registrant Name | PENNANTPARK INVESTMENT CORPORATION |  |  |  |  |
Entity Address, Address Line One | 1691 Michigan Avenue |  |  |  |  |
Entity Address, City or Town | Miami Beach |  |  |  |  |
Entity Address, State or Province | FL |  |  |  |  |
Entity Address, Postal Zip Code | 33319 |  |  |  |  |
City Area Code | 786 |  |  |  |  |
Local Phone Number | 297-9500 |  |  |  |  |
Entity Well-known Seasoned Issuer | No |  |  |  |  |
Entity Emerging Growth Company | false |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |
NAV Per Share | $ 7.11 | $ 7.56 | $ 7.7 | $ 8.98 | $ 9.85 | $ 7.84

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