Summary of significant accounting policies - Additional Information (Details) |
12 Months Ended | |
|---|---|---|
|
Dec. 31, 2020
USD ($)
segment
|
Dec. 31, 2019
USD ($)
|
|
| Accounting Policies [Abstract] | ||
| Joint venture, percent owned | 51.00% | |
| Allowance for doubtful accounts | $ 418,000 | $ 75,000 |
| Impairment of long-lived assets | $ 251,906 | 0 |
| Number of operating segments | segment | 2 | |
| Advertising expense | $ 23,000 | 142,000 |
| Research and development | $ 767,000 | $ 1,460,000 |
| X | ||||||||||
- Definition Percentage Of Owned Joint Venture. No definition available.
|
| X | ||||||||||
- Definition Research And Development Expense, Gross No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of allowance for credit loss on accounts receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|