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Note 16 - Stock Based Compensation - (Details Textual)		1 Months Ended	12 Months Ended				30 Months Ended
Note 16 - Stock Based Compensation - (Details Textual)	Dec. 20, 2016 USD ($) shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2006 shares	Dec. 31, 2019 USD ($) $ / shares shares	Jun. 29, 2017 shares	Feb. 01, 2016 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant						1,500,000
Share-based Payment Arrangement, Expense \| $		$ 63,000
Stock Issued During Period, Shares, Issued for Services			4,440	3,750
Shares Issued, Shares, Share-based Payment Arrangement, before Forfeiture				5,552
Noninterest Expense Directors Fees \| $			$ 570,000	$ 436,000	$ 400,000
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares			$ 10	$ 10			$ 10		$ 10
Warrants and Rights, Intrinsic Value Upon Exercise \| $			$ 1,100,000				$ 1,100,000
Class of Warrant or Right, Outstanding				87,625
Class of Warrant or Right, Expense Recognized \| $				$ 48,000
Share-based Compensation Arrangement by Share-based Payment Award Warrants Assumed Weighted Average Grant Date Fair Value \| $ / shares				$ 2.50
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number			724,300				724,300
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price \| $ / shares			$ 12.55				$ 12.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares, Ending Balance			1,000				1,000
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount \| $			$ 5,000				$ 5,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value \| $			$ 9,000,000				$ 9,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term			1 year 146 days
Share-based Compensation Arrangement by Share-based Payment Award Options, Amended, Number of Shares	330,000	105,250
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term						10 years
Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input				1
Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input				6.5
Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input				0.0504
Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input				0.1319
Common Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			101,000				101,000
Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares			$ 23.96	$ 20
Noninterest Expense Directors Fees \| $			$ 197,000	$ 75,000
Employee [Member]
Share-based Payment Arrangement, Expense \| $				$ 140,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares				$ 25.16
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Vesting, Number of Equal Installments			3	3	3
Share-based Payment Arrangement, Expense \| $			$ 1,000,000	$ 766,000	$ 129,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount \| $		$ 92,000	$ 1,700,000	$ 1,100,000	$ 92,000		$ 1,700,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 328 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares			$ 23.96	$ 20	$ 17
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense \| $	$ 168,000		$ 77,000	$ 119,000	$ 207,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year
The 2017 Equity Incentive Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance								500,000
Share-based Compensation Arrangement by Share-based Payment Award, Grants in Period, Gross							93,525
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			406,475				406,475