Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0001564590-22-018241-index-headers.html | 2022-05-05 16:05:41 | |
| 0001564590-22-018241-index.html | 2022-05-05 16:05:41 | |
| 0001564590-22-018241.txt | 2022-05-05 16:05:41 | |
 0001564590-22-018241-xbrl.zip | 24011 | 2022-05-05 16:05:41 |
| atra-20220505.xsd | 5693 | 2022-05-05 16:05:41 |
| atra-20220505_lab.xml | 19424 | 2022-05-05 16:05:41 |
| atra-20220505_pre.xml | 11584 | 2022-05-05 16:05:41 |
| atra-8k_20220505.htm | 38478 | 2022-05-05 16:05:41 |
| atra-8k_20220505_htm.xml | 3572 | 2022-05-05 16:05:41 |
| atra-ex991_6.htm | 297642 | 2022-05-05 16:05:41 |
| FilingSummary.xml | 1750 | 2022-05-05 16:05:41 |
| Financial_Report.xlsx | 5715 | 2022-05-05 16:05:41 |
| MetaLinks.json | 19145 | 2022-05-05 16:05:41 |
| R1.htm | 40279 | 2022-05-05 16:05:41 |
| report.css | 2767 | 2022-05-05 16:05:41 |
| Show.js | 1084 | 2022-05-05 16:05:41 |