| INTANGIBLE ASSETS | INTANGIBLE ASSETS Intangible assets as of March 31, 2023 and December 31, 2022 consisted of the following: Amortization expense related to continuing operations was $0.56 million and $2.34 million for the three months ended March 31, 2023 and 2022, respectively.
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|  |  |  | (in thousands) |  
|  |  |  | March 31, 2023 |  | December 31, 2022 |  
|  | Estimated Useful
 Life in
 Years
 |  | Gross Carrying
 Amount
 |  | Accumulated Amortization
 |  | Net Carrying
 Value
 |  | Gross Carrying
 Amount
 |  | Accumulated Amortization
 |  | Net Carrying
 Value
 |  
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Amortizing Intangible Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Customer Relationships | 3 to 5 |  | $ | 7,400 |  |  | $ | (7,400) |  |  | $ | — |  |  | $ | 7,400 |  |  | $ | (7,400) |  |  | $ | — |  |  
| Trademarks and Patent | 2 to 8 |  | 4,500 |  |  | (3,554) |  |  | 946 |  |  | 4,500 |  |  | (2,991) |  |  | 1,509 |  |  
| Operating Licenses | 14 |  | 12,239 |  |  | (12,239) |  |  | — |  |  | 12,239 |  |  | (12,239) |  |  | — |  |  
| Total Amortizing Intangible Assets |  |  | 24,139 |  |  | (23,193) |  |  | 946 |  |  | 24,139 |  |  | (22,630) |  |  | 1,509 |  |  
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Non-Amortizing Intangible Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Trade Name | Indefinite |  | 1,350 |  |  | — |  |  | 1,350 |  |  | 1,350 |  |  | — |  |  | 1,350 |  |  
| Total Non-Amortizing Intangible Assets |  |  | 1,350 |  |  | — |  |  | 1,350 |  |  | 1,350 |  |  | — |  |  | 1,350 |  |  
| Total Intangible Assets, Net |  |  | $ | 25,489 |  |  | $ | (23,193) |  |  | $ | 2,296 |  |  | $ | 25,489 |  |  | $ | (22,630) |  |  | $ | 2,859 |  |  |