Note 7 - Long-term Debt (Details Textual) - HSBC Bank Mortgage Loan [Member]	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Instrument, Number of Payments	120
Debt Instrument, Periodic Payment, Total	$ 25,000
Long-term Debt, Total		$ 1,800,000
Debt Instrument, Interest Rate, Stated Percentage		1.86%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		1.75%
Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%

The number of payments for a debt instrument.

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

Amount of the required periodic payments including both interest and principal payments.

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- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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