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 0000768835-18-000030-index-headers.html | 2018-04-03 16:07:45 | |
| 0000768835-18-000030-index.html | 2018-04-03 16:07:45 | |
| 0000768835-18-000030.txt | 2018-04-03 16:07:45 | |
 0000768835-18-000030-xbrl.zip | 269539 | 2018-04-03 16:07:45 |
| big-20180203.xml | 1668273 | 2018-04-03 16:07:45 |
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| big-20180203_cal.xml | 104365 | 2018-04-03 16:07:45 |
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| big-201823x10k.htm | 1787916 | 2018-04-03 16:07:45 |
| big-201823xex1040.htm | 1847613 | 2018-04-03 16:07:45 |
| big-201823xex1041.htm | 420519 | 2018-04-03 16:07:45 |
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| big-201823xex21.htm | 27834 | 2018-04-03 16:07:45 |
| big-201823xex23.htm | 10780 | 2018-04-03 16:07:45 |
| big-201823xex24.htm | 21267 | 2018-04-03 16:07:45 |
| big-201823xex311.htm | 14690 | 2018-04-03 16:07:45 |
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| big-201823xex321.htm | 7308 | 2018-04-03 16:07:45 |
| big-201823xex322.htm | 7373 | 2018-04-03 16:07:45 |
| FilingSummary.xml | 35719 | 2018-04-03 16:07:45 |
| Financial_Report.xlsx | 101305 | 2018-04-03 16:07:45 |
| R1.htm | 28510 | 2018-04-03 16:07:45 |
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| report.css | 2767 | 2018-04-03 16:07:45 |
 secannualreturns18.gif | 20221 | 2018-04-03 16:07:45 |
| Show.js | 1410 | 2018-04-03 16:07:45 |