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|---|---|---|
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| 0000950170-21-000847-index.html | 2021-08-05 06:25:50 | |
| 0000950170-21-000847.txt | 2021-08-05 06:25:50 | |
 0000950170-21-000847-xbrl.zip | 209147 | 2021-08-05 06:25:50 |
| bv-20210630.htm | 2702227 | 2021-08-05 06:25:50 |
| bv-20210630.xsd | 42405 | 2021-08-05 06:25:50 |
| bv-20210630ex31_1.htm | 22973 | 2021-08-05 06:25:50 |
| bv-20210630ex31_2.htm | 23001 | 2021-08-05 06:25:50 |
| bv-20210630ex32_1.htm | 14193 | 2021-08-05 06:25:50 |
| bv-20210630ex32_2.htm | 14216 | 2021-08-05 06:25:50 |
| bv-20210630_cal.xml | 50313 | 2021-08-05 06:25:50 |
| bv-20210630_def.xml | 157077 | 2021-08-05 06:25:50 |
| bv-20210630_htm.xml | 2071935 | 2021-08-05 06:25:50 |
| bv-20210630_lab.xml | 378727 | 2021-08-05 06:25:50 |
| bv-20210630_pre.xml | 290988 | 2021-08-05 06:25:50 |
| FilingSummary.xml | 37123 | 2021-08-05 06:25:50 |
| Financial_Report.xlsx | 80130 | 2021-08-05 06:25:50 |
| MetaLinks.json | 577107 | 2021-08-05 06:25:50 |
| R1.htm | 53764 | 2021-08-05 06:25:50 |
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| report.css | 2767 | 2021-08-05 06:25:50 |
| Show.js | 1085 | 2021-08-05 06:25:50 |