| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4 | Open Document | Open Filing | null | Apr 23, 2025 | Apr 22, 2025 | 000-28542 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jan 8, 2021 | Jan 7, 2021 | 000-28542 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jun 4, 2019 | May 31, 2019 | 000-28542 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Apr 10, 2018 | Apr 4, 2018 | 000-28542 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Dec 6, 2016 | Dec 6, 2016 | 000-28542 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Dec 29, 2015 | Dec 24, 2015 | 000-28542 |