| Form type | Document | Filing | Description | Filing date | Reporting date | File number(s) |
|---|---|---|---|---|---|---|
| 4 | Open Document | Open Filing | Sep 30, 2021 | Sep 28, 2021 | 811-10573 | |
| 4 | Open Document | Open Filing | Aug 12, 2021 | Aug 10, 2021 | 811-10573 | |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 5, 2020 | Aug 4, 2020 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Jul 28, 2020 | Jul 27, 2020 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Jul 1, 2020 | Jun 29, 2020 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 20, 2019 | Aug 19, 2019 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 9, 2019 | Aug 7, 2019 | 000-18548 |
| 4 | Open Document | Open Filing | Feb 15, 2019 | Feb 13, 2019 | 811-07732 | |
| 4 | Open Document | Open Filing | Feb 15, 2019 | Feb 14, 2019 | 811-10573 | |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 2, 2018 | Jul 31, 2018 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 10, 2017 | Aug 8, 2017 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 11, 2016 | Aug 9, 2016 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Jul 29, 2016 | Jul 28, 2016 | 000-18548 |
| 4 | Open Document | Open Filing | OWNERSHIP DOCUMENT | Jun 16, 2016 | Jun 15, 2016 | 811-07732 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Dec 2, 2015 | Dec 1, 2015 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 13, 2015 | Aug 11, 2015 | 000-18548 |
| 4 | Open Document | Open Filing | PRIMARY DOCUMENT | Aug 14, 2014 | Aug 12, 2014 | 000-18548 |
| 4 | Open Document | Open Filing | FORM 4 | Jun 2, 2014 | May 29, 2014 | 001-13828 |