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|---|---|---|
 0000729580-19-000021-index-headers.html | 2019-08-06 14:30:57 | |
| 0000729580-19-000021-index.html | 2019-08-06 14:30:57 | |
| 0000729580-19-000021.txt | 2019-08-06 14:30:57 | |
 0000729580-19-000021-xbrl.zip | 167629 | 2019-08-06 14:30:57 |
| bel10-q.htm | 1539760 | 2019-08-06 14:30:57 |
| belfb-20190630.xml | 1581835 | 2019-08-06 14:30:57 |
| belfb-20190630.xsd | 40518 | 2019-08-06 14:30:57 |
| belfb-20190630_cal.xml | 75590 | 2019-08-06 14:30:57 |
| belfb-20190630_def.xml | 222888 | 2019-08-06 14:30:57 |
| belfb-20190630_lab.xml | 580451 | 2019-08-06 14:30:57 |
| belfb-20190630_pre.xml | 360960 | 2019-08-06 14:30:57 |
| ex31-1.htm | 13738 | 2019-08-06 14:30:57 |
| ex31-2.htm | 14062 | 2019-08-06 14:30:57 |
| ex32-1.htm | 3977 | 2019-08-06 14:30:57 |
| ex32-2.htm | 4451 | 2019-08-06 14:30:57 |
| FilingSummary.xml | 30153 | 2019-08-06 14:30:57 |
| Financial_Report.xlsx | 60330 | 2019-08-06 14:30:57 |
| R1.htm | 34771 | 2019-08-06 14:30:57 |
| R10.htm | 18998 | 2019-08-06 14:30:57 |
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| R32.htm | 68116 | 2019-08-06 14:30:57 |
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| report.css | 2767 | 2019-08-06 14:30:57 |
| Show.js | 1085 | 2019-08-06 14:30:57 |