Note 5 - Loans and Allowance for Loan Losses - TDR Loan Modifications (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Interest Only Payments [Member]
Troubled Debt Restructuring	$ 724	$ 1,001
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		433
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring		300
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring		396
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Reduction of Principal and Interest Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		604
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		1,996
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		204
Performing Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	7,750
Performing Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Only Payments [Member]
Troubled Debt Restructuring		7,579
Performing Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	957
Performing Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member]
Troubled Debt Restructuring		226
Performing Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Extended Maturity [Member] | Home Equity Loan [Member]
Troubled Debt Restructuring	216	218
Performing Financial Instruments [Member] | Interest Only Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	316
Performing Financial Instruments [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	600
Performing Financial Instruments [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	387
Performing Financial Instruments [Member] | Reduction of Principal and Interest Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	586
Performing Financial Instruments [Member] | Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	1,610
Performing Financial Instruments [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	204
Performing Financial Instruments [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	574
Performing Financial Instruments [Member]
Troubled Debt Restructuring	13,924	12,957
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring		2,473
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		232
Nonperforming Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	392
Nonperforming Financial Instruments [Member] | Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member]
Troubled Debt Restructuring		391
Nonperforming Financial Instruments [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	2,374
Nonperforming Financial Instruments [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	232
Nonperforming Financial Instruments [Member]
Troubled Debt Restructuring	2,998	3,096
Residential Portfolio Segment [Member] | Interest Only Payments [Member]
Troubled Debt Restructuring	724	1,001
Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		433
Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring		2,773
Commercial Real Estate Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		232
Commercial Real Estate Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring		396
Commercial Real Estate Portfolio Segment [Member] | Reduction of Principal and Interest Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		604
Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		1,996
Commercial Real Estate Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring		204
Commercial and Industrial Portfolio Segment [Member] | Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	7,750
Commercial and Industrial Portfolio Segment [Member] | Interest Only Payments [Member]
Troubled Debt Restructuring		7,579
Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	1,349
Commercial and Industrial Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member]
Troubled Debt Restructuring		617
Consumer Portfolio Segment [Member] | Extended Maturity [Member] | Home Equity Loan [Member]
Troubled Debt Restructuring	216	218
Interest Only Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	316
Interest Only Payments [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	2,974
Contractual Interest Rate Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	232
Contractual Interest Rate Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	387
Reduction of Principal and Interest Payments [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	586
Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	1,610
Interest Rate Below Market Reduction [Member] | Commercial Real Estate Owner Occupied [Member]
Troubled Debt Restructuring	204
Interest Rate Below Market Reduction [Member] | Commercial Real Estate Nonowner Occupied [Member]
Troubled Debt Restructuring	574
Troubled Debt Restructuring	$ 16,922	$ 16,053