Exercise price per share or per unit of warrants or rights outstanding.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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The number of warrants exercised during the period.

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

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Represents the amount of operating lease expense per year.

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The area leased by certain operating leases.

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Number of stock issued for the exercise of warrants during the period.

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Note 17 - Subsequent Events (Details Textual)									12 Months Ended
Note 17 - Subsequent Events (Details Textual)	Mar. 20, 2021 USD ($)	Mar. 15, 2021 USD ($) ft²	Feb. 05, 2021 $ / shares shares	Jan. 06, 2021 USD ($) shares	Jan. 01, 2021 USD ($) ft²	Aug. 12, 2020 $ / shares shares	Jan. 06, 2020 USD ($) shares	Jan. 06, 2019 USD ($) shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Treasury Stock, Value, Acquired, Cost Method									$ 280,269	$ 71,906
Common Stock Warrants [Member]
Stock Issued During Period, Shares, Warrants Exercised (in shares) \| shares						27,051
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares						$ 3.46
Class of Warrant or Right, Number of Warrants Exercised (in shares) \| shares						60,000
Customer Concentration Risk [Member] \| Revenue from Contract with Customer Benchmark [Member] \| Largest ACH Customer [Member]
Concentration Risk, Percentage									1.12%
Customer Concentration Risk [Member] \| Revenue from Contract with Customer Benchmark [Member] \| Largest ACH Customer [Member] \| ACH and Complementary Service Revenue [Member]
Concentration Risk, Percentage									15.00%
Subsequent Event [Member] \| Debit Arrangement to Finance Purchase of Output Solutions Sorter [Member]
Debt Instrument, Face Amount	$ 165,996
Debt Instrument, Term (Month)	3 years
Debt Instrument, Periodic Payment, Total	$ 4,901.79
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid	4,901.88
Debt Instrument, Annual Periodic Payment	$ 58,821
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Subsequent Event [Member] \| Common Stock Warrants [Member]
Stock Issued During Period, Shares, Warrants Exercised (in shares) \| shares			19,795
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares			$ 5.88
Class of Warrant or Right, Number of Warrants Exercised (in shares) \| shares			30,000
Subsequent Event [Member] \| Austin, TX [Member] \| Lease for Technology Organization [Member]
Lessee, Operating Lease, Term of Contract (Month)					2 years 30 days
Operating Leases, Area Leased (Square Foot) \| ft²					1,890
Operating Lease, Annual Expense					$ 55,755
Subsequent Event [Member] \| San Antonio, TX [Member] \| Incremental Space Leased [Member]
Operating Leases, Area Leased (Square Foot) \| ft²		2,734
Subsequent Event [Member] \| San Antonio, TX [Member] \| Incremental Space Leased [Member] \| Minimum [Member]
Operating Lease, Annual Expense		$ 56,047
Subsequent Event [Member] \| San Antonio, TX [Member] \| Incremental Space Leased [Member] \| Maximum [Member]
Operating Lease, Annual Expense		$ 60,148
Chief Financial Officer [Member]
Treasury Stock, Shares, Acquired (in shares) \| shares							11,860	11,860
Treasury Stock, Value, Acquired, Cost Method							$ 20,636	$ 21,822
Chief Financial Officer [Member] \| Subsequent Event [Member]
Treasury Stock, Shares, Acquired (in shares) \| shares				11,860
Treasury Stock, Value, Acquired, Cost Method				$ 38,545