Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000768835-21-000089-index-headers.html | 2021-06-09 16:02:39 | |
| 0000768835-21-000089-index.html | 2021-06-09 16:02:39 | |
| 0000768835-21-000089.txt | 2021-06-09 16:02:39 | |
 0000768835-21-000089-xbrl.zip | 172572 | 2021-06-09 16:02:39 |
| big-20210501.htm | 803299 | 2021-06-09 16:02:39 |
| big-20210501.xsd | 28835 | 2021-06-09 16:02:39 |
| big-20210501_cal.xml | 52030 | 2021-06-09 16:02:39 |
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| big-202151xex322.htm | 5817 | 2021-06-09 16:02:39 |
| FilingSummary.xml | 20416 | 2021-06-09 16:02:39 |
| Financial_Report.xlsx | 47734 | 2021-06-09 16:02:39 |
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| R10.htm | 18497 | 2021-06-09 16:02:39 |
| R11.htm | 20115 | 2021-06-09 16:02:39 |
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| R18.htm | 17244 | 2021-06-09 16:02:39 |
| R19.htm | 17468 | 2021-06-09 16:02:39 |
| R2.htm | 66006 | 2021-06-09 16:02:39 |
| R20.htm | 11589 | 2021-06-09 16:02:39 |
| R21.htm | 37175 | 2021-06-09 16:02:39 |
| R22.htm | 15332 | 2021-06-09 16:02:39 |
| R23.htm | 12193 | 2021-06-09 16:02:39 |
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| R25.htm | 23634 | 2021-06-09 16:02:39 |
| R26.htm | 33717 | 2021-06-09 16:02:39 |
| R27.htm | 15853 | 2021-06-09 16:02:39 |
| R28.htm | 7172 | 2021-06-09 16:02:39 |
| R29.htm | 15808 | 2021-06-09 16:02:39 |
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| R30.htm | 8536 | 2021-06-09 16:02:39 |
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| R32.htm | 4899 | 2021-06-09 16:02:39 |
| R33.htm | 21876 | 2021-06-09 16:02:39 |
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| R6.htm | 4486 | 2021-06-09 16:02:39 |
| R7.htm | 79734 | 2021-06-09 16:02:39 |
| R8.htm | 17981 | 2021-06-09 16:02:39 |
| R9.htm | 26413 | 2021-06-09 16:02:39 |
| report.css | 2767 | 2021-06-09 16:02:39 |
| Show.js | 1085 | 2021-06-09 16:02:39 |