The ratio applied to the conversion of restricted stock into common stock upon the vesting of restricted stock.

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of new stock issued during the period.

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Note 22 - Stock Compensation Plans (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	May 13, 2014 shares
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense \| $	$ 240	$ 116
Restricted Stock, Vested, Conversion Ratio	1
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	14,457
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount \| $	$ 177
Restricted Stock Units (RSUs) [Member] \| Vesting Immediately [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	4,825
Restricted Stock Units (RSUs) [Member] \| Vesting One Half Each Year for Two Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	9,632
Board of Directors [Member]
Stock Issued During Period, Shares, New Issues (in shares)	3,500
Share-based Payment Arrangement, Expense \| $	$ 50	$ 67
First National Corporation 2014 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)			240,000