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Note 5 - Common Shares and Earnings Per Share - Reconciliation of Company's Common Shares (Details)	12 Months Ended
	Dec. 31, 2019 shares
Common Shares Outstanding, beginning balance (in shares)	39,664,884
Dividends Reinvested (in shares)	29,599
Cash Invested (in shares)	23,740
Vesting of Restricted Stock Units (in shares)	29,100
Restricted Stock Issued to Directors (in shares)	15,700
Directors Deferred Compensation (in shares)	594
Shares Withheld for Individual Income Tax Requirements (in shares)	(55,224)
Common Shares Outstanding, ending balance (in shares)	40,157,591
Performance Awards 2016 [Member]
Executive Stock Performance Awards (2016 awards earned) (in shares)	102,198
At the Market Offering [Member]
At-the-Market Offering (in shares)	347,000

X

- Definition

Represents number of shares of directors deferred compensation.

+ References

No definition available.

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X

- Definition

Represents the number of common shares withheld for individual income tax requirements during the period.

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- Definition

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

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- Definition

Represents the number of restricted shares of common stock vested.

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- Definition

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

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- Definition

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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