Note 5 - Loans and Allowance for Loan Losses - TDRs Pre-Modification and Post-Modification (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Performing Financial Instruments [Member] | Residential Portfolio Segment [Member] | Interest Only Payments [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment			$ 495
TDR’s Performing to Modified Terms Post- Modification Recorded Investment			495
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment			495
TDR’s Performing to Modified Terms Post- Modification Recorded Investment			495
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment
TDR’s Performing to Modified Terms Post- Modification Recorded Investment
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment
TDR’s Performing to Modified Terms Post- Modification Recorded Investment
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment	$ 1,025		1,025
TDR’s Performing to Modified Terms Post- Modification Recorded Investment	1,025		1,025
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment	1,025		1,025
TDR’s Performing to Modified Terms Post- Modification Recorded Investment	1,025		1,025
Performing Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Rate Below Market Reduction [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		574
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		574
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		574
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		574
Performing Financial Instruments [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment	1,025	574	1,520
TDR’s Performing to Modified Terms Post- Modification Recorded Investment	1,025	574	1,520
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment	1,025	574	1,520
TDR’s Performing to Modified Terms Post- Modification Recorded Investment	1,025	574	1,520
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Interest Only Payments [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		226
Nonperforming Financial Instruments [Member] | Commercial Real Estate Portfolio Segment [Member] | Extended Maturity [Member] | Commercial Real Estate Owner Occupied [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment
TDR’s Performing to Modified Terms Post- Modification Recorded Investment
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment
TDR’s Performing to Modified Terms Post- Modification Recorded Investment
Nonperforming Financial Instruments [Member]
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Pre- Modification Recorded Investment		226
TDR’s Performing to Modified Terms Post- Modification Recorded Investment		$ 226