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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Note 3 - Loans - Allowance for Loan Losses by Portfolio Segment and Based on Impairment Evaluation Method (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Jun. 30, 2018	Dec. 31, 2017
Loans						$ 2,577,960	$ 2,409,570
Loans collectively evaluated for impairment						2,570,721	2,401,714
Loans individually evaluated for impairment						7,239	7,380
Balance			$ 24,885	$ 24,007	$ 24,007
Provision for loan losses	$ 1,235	$ 600	1,970	1,500	2,550
Charge-offs			(2,175)		(2,429)
Recoveries			193		757
Balance	24,873		24,873		24,885
Allowance for loans collectively evaluated for impairment						24,196	24,837
Allowance for loans individually evaluated for impairment						677	48
Allowance for loans acquired with deteriorated credit quality	24,873		24,873	24,007	24,885	24,873	24,885
Financial Asset Acquired with Credit Deterioration [Member]
Loans							476
Balance
Balance
Allowance for loans acquired with deteriorated credit quality
Commercial and Industrial Portfolio Segment [Member]
Loans						855,015	779,014
Loans collectively evaluated for impairment						852,566	777,838
Loans individually evaluated for impairment						2,449	1,176
Balance			11,276	10,483	10,483
Provision for loan losses			2,769		2,373
Charge-offs			(1,939)		(1,782)
Recoveries			12		202
Balance	12,118		12,118		11,276
Allowance for loans collectively evaluated for impairment						11,769	11,242
Allowance for loans individually evaluated for impairment						349	34
Allowance for loans acquired with deteriorated credit quality	12,118		11,276	10,483	11,276	12,118	11,276
Commercial and Industrial Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Loans
Balance
Balance
Allowance for loans acquired with deteriorated credit quality
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans						216,068	195,912
Loans collectively evaluated for impairment						215,688	195,248
Loans individually evaluated for impairment						380	664
Balance			1,724	1,923	1,923
Provision for loan losses			214		(199)
Charge-offs
Recoveries
Balance	1,938		1,938		1,724
Allowance for loans collectively evaluated for impairment						1,938	1,724
Allowance for loans individually evaluated for impairment
Allowance for loans acquired with deteriorated credit quality	1,938		1,724	1,923	1,724	1,938	1,724
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Loans
Balance
Balance
Allowance for loans acquired with deteriorated credit quality
Undevelopment Land Portfolio Segment [Member]
Loans						22,156	18,988
Loans collectively evaluated for impairment						21,682	18,514
Loans individually evaluated for impairment						474	474
Balance			521	684	684
Provision for loan losses			(20)		(163)
Charge-offs
Recoveries
Balance	501		501		521
Allowance for loans collectively evaluated for impairment						501	521
Allowance for loans individually evaluated for impairment
Allowance for loans acquired with deteriorated credit quality	501		521	684	521	501	521
Undevelopment Land Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Loans
Balance
Balance
Allowance for loans acquired with deteriorated credit quality
Real Estate Mortgage Portfolio Segment [Member]
Loans						1,441,091	1,376,788
Loans collectively evaluated for impairment						1,437,155	1,371,246
Loans individually evaluated for impairment						3,936	5,066
Balance			11,012	10,573	10,573
Provision for loan losses			(1,104)		383
Charge-offs					(98)
Recoveries			6		154
Balance	9,914		9,914		11,012
Allowance for loans collectively evaluated for impairment						9,586	10,998
Allowance for loans individually evaluated for impairment						328	14
Allowance for loans acquired with deteriorated credit quality	9,914		11,012	10,573	11,012	9,914	11,012
Real Estate Mortgage Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Loans							476
Balance
Balance
Allowance for loans acquired with deteriorated credit quality
Consumer Portfolio Segment [Member]
Loans						43,630	38,868
Loans collectively evaluated for impairment						43,630	38,868
Loans individually evaluated for impairment
Balance			352	344	344
Provision for loan losses			111		156
Charge-offs			(236)		(549)
Recoveries			175		401
Balance	402		402		352
Allowance for loans collectively evaluated for impairment						402	352
Allowance for loans individually evaluated for impairment
Allowance for loans acquired with deteriorated credit quality	402		352	$ 344	352	402	352
Consumer Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Loans
Balance
Balance
Allowance for loans acquired with deteriorated credit quality