Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000768835-20-000159-index-headers.html | 2020-12-09 16:03:04 | |
| 0000768835-20-000159-index.html | 2020-12-09 16:03:04 | |
| 0000768835-20-000159.txt | 2020-12-09 16:03:04 | |
 0000768835-20-000159-xbrl.zip | 285855 | 2020-12-09 16:03:04 |
| big-20201031.htm | 1252652 | 2020-12-09 16:03:04 |
| big-20201031.xsd | 29699 | 2020-12-09 16:03:04 |
| big-20201031xex101.htm | 534666 | 2020-12-09 16:03:04 |
| big-20201031xex311.htm | 11009 | 2020-12-09 16:03:04 |
| big-20201031xex312.htm | 11519 | 2020-12-09 16:03:04 |
| big-20201031xex321.htm | 5275 | 2020-12-09 16:03:04 |
| big-20201031xex322.htm | 5792 | 2020-12-09 16:03:04 |
| big-20201031_cal.xml | 56952 | 2020-12-09 16:03:04 |
| big-20201031_def.xml | 237022 | 2020-12-09 16:03:04 |
| big-20201031_htm.xml | 861872 | 2020-12-09 16:03:04 |
| big-20201031_lab.xml | 478523 | 2020-12-09 16:03:04 |
| big-20201031_pre.xml | 294101 | 2020-12-09 16:03:04 |
| FilingSummary.xml | 22275 | 2020-12-09 16:03:04 |
| Financial_Report.xlsx | 58010 | 2020-12-09 16:03:04 |
| MetaLinks.json | 475738 | 2020-12-09 16:03:04 |
| R1.htm | 52294 | 2020-12-09 16:03:04 |
| R10.htm | 18405 | 2020-12-09 16:03:04 |
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| R31.htm | 9469 | 2020-12-09 16:03:04 |
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| R8.htm | 20600 | 2020-12-09 16:03:04 |
| R9.htm | 30356 | 2020-12-09 16:03:04 |
| report.css | 2767 | 2020-12-09 16:03:04 |
| Show.js | 1085 | 2020-12-09 16:03:04 |