Note 8 - Loans - Average Balance and Interest Income Recognized Related to Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Average Recorded Investment	$ 115,085	$ 125,627
Interest Income Recognized	947	1,078
Commercial Portfolio Segment [Member]
Average Recorded Investment	37,936	45,183
Interest Income Recognized	256	334
Real Estate Construction Portfolio Segment [Member]
Average Recorded Investment	4,815	8,137
Interest Income Recognized
Commercial Real Estate Portfolio Segment [Member]
Average Recorded Investment	59,070	58,598
Interest Income Recognized	603	644
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Average Recorded Investment	13,264	13,709
Interest Income Recognized	$ 88	$ 100

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

Name:	us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration