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Note 20 - Regulatory Matters (Details Textual) - USD ($) $ / shares in Units, $ in Millions											3 Months Ended		12 Months Ended
	Mar. 17, 2021	Jan. 14, 2021	Dec. 16, 2020	Oct. 15, 2020	Sep. 16, 2020	Jul. 16, 2020	Jun. 17, 2020	Apr. 16, 2020	Mar. 18, 2020	Jan. 16, 2020	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	May 31, 2019	Dec. 31, 2009
Capital Conservation Buffer											2.50%		2.50%
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy to Risk Weighted Assets											0.070		0.070
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets											0.085		0.085
Capital Required for Capital Adequacy to Risk Weighted Assets											0.105		0.105
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval											$ 85.7		$ 85.7
Common Stock, Dividends, Per Share, Declared (in dollars per share)				$ 0.28		$ 0.28		$ 0.28		$ 0.28
Stock Repurchase Program, Authorized Amount															$ 20.0
Stock Repurchased During Period, Shares (in shares)											14,000	222,000
Stock Repurchased During Period, Value											$ 0.3	$ 6.3
Treasury Stock Acquired, Average Cost Per Share (in dollars per share)											$ 22.05	$ 28.25
Stock Repurchase Program, Remaining Authorized Repurchase Amount											$ 10.0		10.0
Preferred Securities of Subsidiary Trust											45.5		$ 45.5	$ 44.8
Maximum Restricted Core Element Allowed in Tier One Capital Percent													25.00%
Maximum Level of Consolidated Aggregate Assets Allowing for Inclusion of Trust Preferred Securities in Tier One Capital																$ 15,000.0
Trust Preferred Securities Included in Tier One Capital											$ 45.5		$ 45.5	$ 44.8
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)			$ 0.28		$ 0.28		$ 0.28		$ 0.28
Forecast [Member]
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)	$ 0.29
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)		$ 0.29

X

- Definition

An additional amount held in risk-based capital designed to ensure that banks build up capital buffers outside periods of stress which can be drawn down as losses are incurred. The requirement is based on simple capital conservation rules designed to avoid breaches of minimum capital requirements.

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The minimum common equity tier one capital ratio (common equity tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under the Dodd-Frank Act.

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The maximum amount of restricted core elements allowed in tier one capital expressed as a percent.

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Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies.

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Trust preferred securities held by the trust that are included in Tier One Capital and subject to certain limitations.

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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
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Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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