| 8-K | Report of unscheduled material events or corporate event | Oct 3, 2019 |     |
| 8-K | Report of unscheduled material events or corporate event | Sep 9, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | Aug 22, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | Aug 5, 2019 | |
| 10-Q | Quarterly report which provides a continuing view of a company's financial position | Aug 5, 2019 |   |
| DEFA14A | Additional proxy soliciting materials - definitive | Jul 26, 2019 | |
| DEF 14A | Official notification to shareholders of matters to be brought to a vote ("Proxy") | Jul 26, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | Jul 26, 2019 | |
| SC 13D/A | Amendment to a SC 13D filing | Jul 25, 2019 | |
| 10-K/A | Amendment to a previously filed 10-K | Jul 24, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | Jul 22, 2019 | |
| SC 13D/A | Amendment to a SC 13D filing | Jul 17, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | Jun 28, 2019 | |
| 8-K/A | Amendment to a previously filed 8-K | Jun 28, 2019 | |
| S-8 | Securities offered to employees pursuant to employee benefit plans | Jun 4, 2019 | |
| SC 13G | Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions | Jun 3, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 4 | Statement of changes in beneficial ownership of securities | May 20, 2019 | |
| 8-K | Report of unscheduled material events or corporate event | May 16, 2019 | |
