Note 11 - Revenue Recognition - Noninterest Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Noninterest income (in-scope of Topic 606)		$ 855	$ 739	$ 2,399	$ 2,145
Noninterest income (out-of-scope of Topic 606)	[1]	207	1,535	610	1,851
Total noninterest income		1,062	2,274	3,009	3,996
Maintenance Fees [Member]
Noninterest income (in-scope of Topic 606)		38	40	114	118
Overdraft Fees [Member]
Noninterest income (in-scope of Topic 606)		417	341	1,100	965
Other Fees [Member]
Noninterest income (in-scope of Topic 606)		73	66	214	207
Electronic Banking Fees [Member]
Noninterest income (in-scope of Topic 606)		$ 327	$ 292	$ 971	$ 855

[1] Noninterest income items that are out-of-scope include net realized gains (losses) on sales of securities, net gains (losses) on sales of loans, earnings on bank-owned life insurance and certain other noninterest income items.