| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4 | Open Document | Open Filing | May 25, 2021 | May 21, 2021 | 000-24249 | |
| 4 | Open Document | Open Filing | Dec 2, 2020 | Dec 1, 2020 | 000-24249 | |
| 3 | Open Document | Open Filing | Dec 2, 2020 | Dec 1, 2020 | 000-24249 | |
| 3 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Oct 20, 2017 | Oct 2, 2017 | 000-53601 |