Note 5 - Loans Receivable and Allowance for Loan and Lease Losses - Non-accrual Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Business Activities Loans [Member]
Non-accruing loans	$ 19,186	$ 3,778
Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	3,525
Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	2,006	3,028
Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	4,681	748
Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	174	2
Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	8,800
Substandard [Member] | Business Activities Loans [Member]
Non-accruing loans	19,186
Substandard [Member] | Acquired Loans [Member]
Non-accruing loans		3,778
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	3,525
Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Acquired Loans [Member]
Non-accruing loans		3,028
Substandard [Member] | Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	2,006	3,028
Substandard [Member] | Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	4,681	748
Substandard [Member] | Commercial Portfolio Segment [Member] | Acquired Loans [Member]
Non-accruing loans		748
Substandard [Member] | Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	174	2
Substandard [Member] | Consumer Portfolio Segment [Member] | Acquired Loans [Member]
Non-accruing loans		2
Substandard [Member] | Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Non-accruing loans	8,800	3,778
Substandard [Member] | Non-Accrual Loans [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	18,384
Performing (accruing) loans, current	802
Substandard [Member] | Non-Accrual Loans [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		3,778
Performing (accruing) loans, current		0
Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	3,525
Performing (accruing) loans, current	0
Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		3,028
Performing (accruing) loans, current		0
Substandard [Member] | Non-Accrual Loans [Member] | Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	2,006
Performing (accruing) loans, current	0
Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	3,956
Performing (accruing) loans, current	725
Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		748
Performing (accruing) loans, current		0
Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	97
Performing (accruing) loans, current	77
Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		2
Performing (accruing) loans, current		0
Substandard [Member] | Non-Accrual Loans [Member] | Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	8,800
Performing (accruing) loans, current	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	1,580
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	1,580
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	101
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	0
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	15
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	86
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due
Financing Receivables, 60 to 89 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	16,703
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		3,778
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	1,945
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		3,028
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Residential Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	2,006
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	3,941
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Commercial Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		748
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	11
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Consumer Portfolio Segment [Member] | Acquired Loans [Member]
Performing (accruing) loans, past due		$ 2
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Substandard [Member] | Non-Accrual Loans [Member] | Construction Portfolio Segment [Member] | Business Activities Loans [Member]
Performing (accruing) loans, past due	$ 8,800