Income taxes (Q3) (Details) - USD ($) |
9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Income taxes [Abstract] | ||||
| Current income tax expense | $ 0 | $ 0 | $ 0 | $ 0 |
| Deferred income tax expense | $ 0 | $ 0 | $ 0 | 0 |
| Effective tax rate | 0.00% | 0.00% | ||
| Accrued interest and penalties related to uncertain tax positions | $ 0 | $ 0 | $ 0 | |
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- References No definition available.
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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