| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4/A | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jul 23, 2021 | Jul 21, 2021 | 000-26495 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jul 23, 2021 | Jul 21, 2021 | 000-26495 |
| 4 | Open Document | Open Filing | Jan 6, 2021 | Jan 4, 2021 | 000-26495 | |
| 4 | Open Document | Open Filing | Jan 8, 2020 | Jan 6, 2020 | 000-26495 | |
| 4 | Open Document | Open Filing | FORM 4 SUBMISSION | Nov 8, 2019 | Nov 6, 2019 | 000-26495 |
| 4 | Open Document | Open Filing | Jan 24, 2019 | Jan 22, 2019 | 000-26495 | |
| 3 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jan 7, 2019 | Jan 1, 2019 | 000-26495 |