Note 3 - Fair Value Measurements (FY) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Sep. 30, 2020	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 452,301	$ 313,737	$ 504,940
Percentage Increase in The Expected Term	10.00%
Percentage Increase in Warrant Liability with Increase in Expected Term	3.00%
Percentage Decrease in Expected Term	10.00%
Percentage Decrease in Warrant Liability with Decrease in Expected Term	3.00%
Percentage Increase in The Stock Price	10.00%
Percentage Increase in Warrant Liability with Increase in Stock Price	30.00%
Percentage Decrease in The Stock Price	10.00%
Percentage Decrease in Warrant Liability with Decrease in Stock Price	26.00%
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 0	0	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0	$ 0

The percentage decrease in expected term that would have significant effect to the warrant liability.

No definition available.

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- Definition

The percentage decrease in the stock price that would have significant effect to the warrant liability.

+ References

No definition available.

+ Details

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- Definition

The percnetage decrease in warrant liability with the 10% decrease in expected term during period.

+ References

No definition available.

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- Definition

The percentage decrease in warrant liability with the 10% decrease in stock price during period.

+ References

No definition available.

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- Definition

The percentage in increase in the expected term that would have significant effect to the warrant liability.

+ References

No definition available.

+ Details

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- Definition

The percentage increase in the stock price that would have significant effect to the warrant liability.

+ References

No definition available.

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- Definition

The percentage increase in warrant liability with the 10% increase in expected term during period.

+ References

No definition available.

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- Definition

The percentage increase in warrant liability with the 10% increase in stock price during period.

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

+ References

No definition available.

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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