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Note 5 - Common Shares and Earnings Per Share - Reconciliation of Company's Common Shares (Details)	9 Months Ended
	Sep. 30, 2020 shares
Common Shares Outstanding, beginning balance (in shares)	40,157,591
Dividends Reinvested (in shares)	102,042
Cash Invested (in shares)	88,636
Vesting of Restricted Stock Units (in shares)	35,720
Cash Invested (in shares)	29,894
Dividends Reinvested (in shares)	7,906
Restricted Stock Issued to Directors (in shares)	17,400
Directors Deferred Compensation (in shares)	612
Shares Withheld for Individual Income Tax Requirements (in shares)	(38,217)
Common Shares Outstanding, ending balance (in shares)	41,052,165
Performance Awards 2017 [Member]
Executive Stock Performance Awards (2017 awards earned) (in shares)	62,497
At the Market Offering [Member]
At-the-Market Offering (in shares)	588,084

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- Definition

Represents number of shares of directors deferred compensation.

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Number of shares issued as resulted of dividends reinvestment during the period from a employee stock purchase plan.

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Represents the number of shares for cash invested under dividend reinvestment and share purchase plan.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Number of new stock issued during the period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number, before forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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