Prepaid and other assets - Schedule of Prepaid and Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Miscellaneous other receivables
Total	$ 36,531	$ 34,052
Thereof current	36,189	33,750
Thereof non‑current	342	302
Prepaid expenses
Total	4,529	3,814
Thereof current	1,170	1,188
Thereof non‑current	3,359	2,626
Total
Total	41,059	37,866
Thereof current	37,358	34,938
Thereof non‑current	$ 3,701	$ 2,928

Other Receivables, Net, Noncurrent

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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