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Accrued expenses and other current liabilities (Tables) | 9 Months Ended
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Sep. 30, 2025
Accrued expenses and other current liabilities |
Schedule of elements of accrued expenses and other current liabilities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, |  | December 31,
​ | ​ | 2025 | ​ | 2024
​ | ​ | (unaudited) | ​ | ​ | ​
(in thousands) | ​ |  | ​ | ​ |  | ​
Accrued expenses | ​ | $ | 17,246 | ​ | $ | 12,320
Cylinder deposits | ​ |  | 22,783 | ​ |  | 19,426
Lease obligations | ​ |  | 2,049 | ​ |  | 1,961
Other current liabilities | ​ |  | 124 | ​ |  | 106
Total | ​ | $ | 42,202 | ​ | $ | 33,813
​

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- Definition Tabular disclosure of the (a) carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business (accounts payable); (b) other payables; and (c) accrued liabilities. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). An alternative caption includes accrued expenses. + References No definition available. + Details
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