| Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] |
| | | Years Ended December 31, | |
| | | 2025 | | | 2024 | | | 2023 | |
| Numerator: | | | | | | | | | | | | |
| Net earnings attributable to Bel shareholders | | $ | 61,536 | | | $ | 40,960 | | | $ | 73,831 | |
| Less dividends declared: | | | | | | | | | | | | |
| Class A | | | 508 | | | | 508 | | | | 512 | |
| Class B | | | 2,957 | | | | 2,931 | | | | 2,997 | |
| Undistributed earnings | | $ | 58,071 | | | $ | 37,521 | | | $ | 70,322 | |
| | | | | | | | | | | | | |
| Undistributed earnings allocation: | | | | | | | | | | | | |
| Class A undistributed earnings | | $ | 9,329 | | | $ | 6,064 | | | $ | 11,318 | |
| Class B undistributed earnings | | | 48,742 | | | | 31,457 | | | | 59,004 | |
| Total undistributed earnings | | $ | 58,071 | | | $ | 37,521 | | | $ | 70,322 | |
| | | | | | | | | | | | | |
| Net earnings allocation: | | | | | | | | | | | | |
| Class A net earnings | | $ | 9,837 | | | $ | 6,572 | | | $ | 11,830 | |
| Class B net earnings | | | 51,699 | | | | 34,388 | | | | 62,001 | |
| Net earnings | | $ | 61,536 | | | $ | 40,960 | | | $ | 73,831 | |
| | | | | | | | | | | | | |
| Denominator: | | | | | | | | | | | | |
| Weighted average shares outstanding: | | | | | | | | | | | | |
| Class A - Basic and Diluted | | | 2,115 | | | | 2,124 | | | | 2,142 | |
| Class B - Basic | | | 10,525 | | | | 10,491 | | | | 10,634 | |
| Class B - Diluted | | | 10,546 | | | | 10,491 | | | | 10,634 | |
| | | | | | | | | | | | | |
| Net earnings per share attributable to Bel shareholders: | | | | | | | | | | | | |
| Class A - Basic and Diluted | | $ | 4.65 | | | $ | 3.10 | | | $ | 5.52 | |
| Class B - Basic | | $ | 4.91 | | | $ | 3.28 | | | $ | 5.83 | |
| Class B - Diluted | | $ | 4.90 | | | $ | 3.28 | | | $ | 5.83 | |
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