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Commitments and contingencies (Tables) | 12 Months Ended
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Dec. 31, 2024
Commitments and contingencies |
Schedule of key properties utilizes leased facilities and operates equipment under non-cancelable operating leases | ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ | ​ |  | Lease
​ | ​ | Annual | ​ | Expiration
Location | ​ | Rent | ​ | Date
Baton Rouge, Louisiana | ​ | $ | 31,000 |  | 7/2026
Champaign, Illinois | ​ | $ | 661,000 |  | 12/2027
Champaign, Illinois (2nd location) | ​ | $ | 349,000 | ​ | 9/2026
Charlotte, North Carolina | ​ | $ | 37,000 |  | 5/2025
Escondido, California | ​ | $ | 249,000 |  | 6/2027
Long Beach, California | ​ | $ | 28,800 |  | 2/2025*
Ontario, California | ​ | $ | 180,000 |  | 12/2027
Riverside, California | ​ | $ | 27,000 |  | Month to Month
Rantoul, Illinois | ​ | $ | 36,000 | ​ | Month to Month
Smyrna, Georgia | ​ | $ | 501,400 |  | 7/2030
Stony Point, New York | ​ | $ | 122,000 |  | 6/2026
Woodcliff Lake, New Jersey | ​ | $ | 315,000 | ​ | 8/2027
​ *Lease was renewed on March 3, 2025

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