Nature of business and summary of significant accounting policies - Goodwill (Details) - USD ($) |
9 Months Ended | 12 Months Ended | |
|---|---|---|---|
Sep. 30, 2020 |
Dec. 31, 2019 |
Dec. 19, 2019 |
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| Business Combination, Description [Abstract] | |||
| Goodwill | $ 18,614,000 | $ 18,614,000 | |
| Goodwill impairment | $ 0 | 0 | |
| Halo | |||
| Business Combination, Description [Abstract] | |||
| Goodwill | $ 18,600,000 | $ 18,614,000 |
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- References No definition available.
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Details
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