Commitments and contingencies - Operating Lease Obligations (Details) - USD ($) |
12 Months Ended | |
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Dec. 31, 2019 |
Dec. 31, 2018 |
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| Office space and warehouse facilities | ||
| Operating Leased Assets [Line Items] | ||
| Lease expense | $ 744,781 | $ 755,579 |
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- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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