Note 5 - Related Party Transactions - Summarizes the Note (Details) - Boyalife Asset Holding II [Member] - Convertible Debt [Member] - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2018	Apr. 16, 2018
Debt Instrument, Maturity Date	Mar. 06, 2022	Mar. 06, 2022
State interest rate	22.00%	22.00%
Conversion price (in dollars per share)	$ 1.80	$ 1.80	$ 1.80	$ 16.10
Face value	$ 10,000,000	$ 10,000,000
Remaining debt discount	(2,410,000)	(4,065,000)
Carrying Value	$ 7,590,000	$ 5,935,000

The price per share of the conversion feature embedded in the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount, after accumulated amortization, of debt discount.

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The amount for notes payable (written promise to pay), due to related parties.

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