| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4 | Open Document | Open Filing | Oct 31, 2022 | Oct 27, 2022 | 000-15905 | |
| 4 | Open Document | Open Filing | May 16, 2022 | May 12, 2022 | 000-15905 | |
| 4 | Open Document | Open Filing | May 1, 2020 | Apr 30, 2020 | 000-15905 | |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Oct 22, 2018 | Oct 18, 2018 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jan 2, 2018 | Dec 28, 2017 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | May 22, 2017 | May 19, 2017 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Oct 13, 2016 | Oct 12, 2016 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jun 10, 2016 | Jun 8, 2016 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jan 15, 2016 | Jan 13, 2016 | 000-15905 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Jun 16, 2015 | Jun 15, 2015 | 000-15905 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Dec 17, 2014 | Dec 17, 2014 | 000-15905 |
| 3 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Aug 27, 2014 | Jun 4, 2014 | 000-15905 |