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|---|---|---|
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| 0000950170-22-000701-index.html | 2022-02-03 06:11:37 | |
| 0000950170-22-000701.txt | 2022-02-03 06:11:37 | |
 0000950170-22-000701-xbrl.zip | 212321 | 2022-02-03 06:11:37 |
| bv-20211231.htm | 2231615 | 2022-02-03 06:11:37 |
| bv-20211231.xsd | 48522 | 2022-02-03 06:11:37 |
| bv-20211231_cal.xml | 51129 | 2022-02-03 06:11:37 |
| bv-20211231_def.xml | 196299 | 2022-02-03 06:11:37 |
| bv-20211231_htm.xml | 1788296 | 2022-02-03 06:11:37 |
| bv-20211231_lab.xml | 446059 | 2022-02-03 06:11:37 |
| bv-20211231_pre.xml | 356124 | 2022-02-03 06:11:37 |
| bv-ex10_2.htm | 200207 | 2022-02-03 06:11:37 |
| bv-ex31_1.htm | 19554 | 2022-02-03 06:11:37 |
| bv-ex31_2.htm | 19584 | 2022-02-03 06:11:37 |
| bv-ex32_1.htm | 9422 | 2022-02-03 06:11:37 |
| bv-ex32_2.htm | 10045 | 2022-02-03 06:11:37 |
| FilingSummary.xml | 39309 | 2022-02-03 06:11:37 |
| Financial_Report.xlsx | 80702 | 2022-02-03 06:11:37 |
| MetaLinks.json | 669813 | 2022-02-03 06:11:37 |
| R1.htm | 53712 | 2022-02-03 06:11:37 |
| R10.htm | 21259 | 2022-02-03 06:11:37 |
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| R9.htm | 13074 | 2022-02-03 06:11:37 |
| report.css | 2767 | 2022-02-03 06:11:37 |
| Show.js | 1085 | 2022-02-03 06:11:37 |