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The number of non-consolidated subsidiaries formed for the issuance of trust preferred securities.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Note 1 - Nature of Business and Significant Accounting Policies (Details)		12 Months Ended
	Sep. 27, 2017	Dec. 31, 2018 USD ($) subsidiary shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Jan. 01, 2019	Sep. 30, 2018 USD ($)
Number of subsidiaries commercial banks \| subsidiary		5
Number of Non-Consolidated Subsidiaries Issuing Trust Preferred Securities \| subsidiary		6
Cash Reserve Deposit Required and Made		$ 33,372,000	$ 41,803,000
Initial Direct Leasing Costs As a Percentage of Cost		5.50%
Financing Receivable, Lines of Credit Maximum Term		1 year
Commercial Real Estate Owner Occupied, Percentage		28.00%	26.00%
Lending Threshold Requiring Additional Loan Review		$ 1,000,000
Goodwill, Impaired, Accumulated Impairment Loss						$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number \| shares		358,270	354,269	385,372
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		$ 7,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		6,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 365,107	$ 1,005,193	$ 1,525,902
Preferred Stock, Shares Authorized \| shares		250,000	250,000
Preferred Stock, Shares Outstanding \| shares		0	0
Allocated Share-based Compensation Expense		$ 1,443,346	$ 1,187,036	947,174
AOCI to retained earnings		304,000
Accounting Standards Update 2016-02 [Member] \| Scenario, Forecast [Member]
Initial Direct Leasing Costs As a Percentage of Cost					4.90%
Employee Stock Option
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 704,659
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 7 months 28 days
Allocated Share-based Compensation Expense		$ 471,849	554,435	424,904
In The Money Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number \| shares		411,030
Restricted Stock
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized		$ 1,976,929
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 6 months 4 days
Allocated Share-based Compensation Expense		$ 856,731	$ 552,907	$ 460,853
Guaranty Bank and Trust Company [Member]
Debt Instrument, Term	4 years
Subsidiaries [Member] \| Fixed Rate Residential Mortgage [Member]
Financing Receivable, Term		15 years
Commercial Portfolio Segment [Member]
Financing Receivable, Term Loans, Generally Maximum Term		7 years
Commercial Real Estate Portfolio Segment [Member] \| Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loan and Leases Receivable, Lending Limits Percent		300.00%
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loan and Leases Receivable, Lending Limits Percent		100.00%
Minimum
Residual Value Percent of Cost		3.00%
Minimum \| Subsidiaries [Member] \| Adjustable Rate Residential Mortgage [Member]
Financing Receivable, Term		1 year
Minimum \| Commercial Portfolio Segment [Member] \| Term Loan [Member]
Financing Receivable, Term		3 years
Maximum
Residual Value Percent of Cost		25.00%
Permanent loans term		20 years
Maximum \| Subsidiaries [Member] \| Adjustable Rate Residential Mortgage [Member]
Financing Receivable, Term		5 years
Maximum \| Special Mention [Member]
Financing Receivable, Credit Weaknesses Borrowers, Term		365 days
Maximum \| Commercial Portfolio Segment [Member] \| Term Loan [Member]
Financing Receivable, Term		5 years
Core Deposits [Member]
Estimated useful life		10 years
Customer Lists [Member]
Estimated useful life		15 years