Note 3 - Loans and Allowance for Loan Losses - Acquired Impaired Loans Accretable Yield (Details) - USD ($)		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Balance at beginning of period		$ 1,274,000	$ 1,404,000
Additions		2,000	0
Accretion income		(119,000)	(131,000)
Net reclassification from nonaccretable to accretable		121,000	86,000
Reductions (1)	[1]	(8,000)	(40,000)
Balance at end of period		$ 1,270,000	$ 1,319,000

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