Parent Directory| Name | Size | Last Modified |
|---|---|---|
 0000729580-17-000012-index-headers.html | 2017-05-05 12:37:05 | |
| 0000729580-17-000012-index.html | 2017-05-05 12:37:05 | |
| 0000729580-17-000012.txt | 2017-05-05 12:37:05 | |
 0000729580-17-000012-xbrl.zip | 104325 | 2017-05-05 12:37:05 |
| bel10-q.htm | 625658 | 2017-05-05 12:37:05 |
| belfb-20170331.xml | 628177 | 2017-05-05 12:37:05 |
| belfb-20170331.xsd | 31544 | 2017-05-05 12:37:05 |
| belfb-20170331_cal.xml | 55580 | 2017-05-05 12:37:05 |
| belfb-20170331_def.xml | 159436 | 2017-05-05 12:37:05 |
| belfb-20170331_lab.xml | 431195 | 2017-05-05 12:37:05 |
| belfb-20170331_pre.xml | 253860 | 2017-05-05 12:37:05 |
| ex31-1.htm | 11342 | 2017-05-05 12:37:05 |
| ex31-2.htm | 11923 | 2017-05-05 12:37:05 |
| ex32-1.htm | 3564 | 2017-05-05 12:37:05 |
| ex32-2.htm | 3961 | 2017-05-05 12:37:05 |
| FilingSummary.xml | 24863 | 2017-05-05 12:37:05 |
| Financial_Report.xlsx | 46971 | 2017-05-05 12:37:05 |
| R1.htm | 29536 | 2017-05-05 12:37:05 |
| R10.htm | 14529 | 2017-05-05 12:37:05 |
| R11.htm | 14536 | 2017-05-05 12:37:05 |
| R12.htm | 20982 | 2017-05-05 12:37:05 |
| R13.htm | 31576 | 2017-05-05 12:37:05 |
| R14.htm | 7840 | 2017-05-05 12:37:05 |
| R15.htm | 10147 | 2017-05-05 12:37:05 |
| R16.htm | 23749 | 2017-05-05 12:37:05 |
| R17.htm | 58125 | 2017-05-05 12:37:05 |
| R18.htm | 9724 | 2017-05-05 12:37:05 |
| R19.htm | 39328 | 2017-05-05 12:37:05 |
| R2.htm | 84584 | 2017-05-05 12:37:05 |
| R20.htm | 7145 | 2017-05-05 12:37:05 |
| R21.htm | 18465 | 2017-05-05 12:37:05 |
| R22.htm | 43662 | 2017-05-05 12:37:05 |
| R23.htm | 14791 | 2017-05-05 12:37:05 |
| R24.htm | 19269 | 2017-05-05 12:37:05 |
| R25.htm | 33158 | 2017-05-05 12:37:05 |
| R26.htm | 22702 | 2017-05-05 12:37:05 |
| R27.htm | 57087 | 2017-05-05 12:37:05 |
| R28.htm | 33652 | 2017-05-05 12:37:05 |
| R29.htm | 7653 | 2017-05-05 12:37:05 |
| R3.htm | 25466 | 2017-05-05 12:37:05 |
| R30.htm | 24358 | 2017-05-05 12:37:05 |
| R31.htm | 28848 | 2017-05-05 12:37:05 |
| R32.htm | 12081 | 2017-05-05 12:37:05 |
| R33.htm | 21780 | 2017-05-05 12:37:05 |
| R34.htm | 29920 | 2017-05-05 12:37:05 |
| R35.htm | 20660 | 2017-05-05 12:37:05 |
| R36.htm | 21015 | 2017-05-05 12:37:05 |
| R37.htm | 39048 | 2017-05-05 12:37:05 |
| R38.htm | 23643 | 2017-05-05 12:37:05 |
| R39.htm | 29241 | 2017-05-05 12:37:05 |
| R4.htm | 43814 | 2017-05-05 12:37:05 |
| R40.htm | 6794 | 2017-05-05 12:37:05 |
| R41.htm | 27405 | 2017-05-05 12:37:05 |
| R42.htm | 12351 | 2017-05-05 12:37:05 |
| R5.htm | 21105 | 2017-05-05 12:37:05 |
| R6.htm | 10257 | 2017-05-05 12:37:05 |
| R7.htm | 77986 | 2017-05-05 12:37:05 |
| R8.htm | 21999 | 2017-05-05 12:37:05 |
| R9.htm | 44956 | 2017-05-05 12:37:05 |
| report.css | 2767 | 2017-05-05 12:37:05 |
| Show.js | 1410 | 2017-05-05 12:37:05 |