Note 3 - Loans and Allowance for Loan Losses - Acquired Impaired Loans Accretable Yield (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Balance at beginning of period		$ 1,464,000	$ 6,319,000	$ 1,726,000	$ 5,193,000
Additions		220,000	0	221,000	21,000
Accretion income		(140,000)	(674,000)	(287,000)	(1,354,000)
Net reclassification from nonaccretable to accretable		184,000	1,193,000	247,000	3,565,000
Reductions	[1]	(70,000)	(236,000)	(249,000)	(823,000)
Balance at end of period		$ 1,658,000	$ 6,602,000	$ 1,658,000	$ 6,602,000

[1] Reductions primarily reflect the result of exit events, including loan payoffs and charge-offs.