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|---|---|---|
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| 0000950170-22-007529-index.html | 2022-05-05 06:18:18 | |
| 0000950170-22-007529.txt | 2022-05-05 06:18:18 | |
 0000950170-22-007529-xbrl.zip | 236184 | 2022-05-05 06:18:18 |
| bv-20220331.htm | 3155342 | 2022-05-05 06:18:18 |
| bv-20220331.xsd | 49052 | 2022-05-05 06:18:18 |
| bv-20220331_cal.xml | 51332 | 2022-05-05 06:18:18 |
| bv-20220331_def.xml | 204863 | 2022-05-05 06:18:18 |
| bv-20220331_htm.xml | 2407785 | 2022-05-05 06:18:18 |
| bv-20220331_lab.xml | 451209 | 2022-05-05 06:18:18 |
| bv-20220331_pre.xml | 364117 | 2022-05-05 06:18:18 |
| bv-ex31_1.htm | 21053 | 2022-05-05 06:18:18 |
| bv-ex31_2.htm | 20465 | 2022-05-05 06:18:18 |
| bv-ex32_1.htm | 10092 | 2022-05-05 06:18:18 |
| bv-ex32_2.htm | 10799 | 2022-05-05 06:18:18 |
| FilingSummary.xml | 39498 | 2022-05-05 06:18:18 |
| Financial_Report.xlsx | 85771 | 2022-05-05 06:18:18 |
| MetaLinks.json | 675953 | 2022-05-05 06:18:18 |
| R1.htm | 53890 | 2022-05-05 06:18:18 |
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| R9.htm | 13328 | 2022-05-05 06:18:18 |
| report.css | 2767 | 2022-05-05 06:18:18 |
| Show.js | 1085 | 2022-05-05 06:18:18 |