Note 9 - Benefit Plans - Restricted Stock (Details) - Restricted Stock [Member]	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Balance of shares non-vested (in shares) | shares	24,378
Balance of shares non-vested, weighted average grant-date price (in dollars per share) | $ / shares	$ 22.75
Granted (in shares) | shares	14,366
Granted, weighted average grant-date price (in dollars per share) | $ / shares	$ 23.50
Vested (in shares) | shares	(10,964)
Vested, weighted average grant-date price (in dollars per share) | $ / shares	$ 22.23
Forfeited (in shares) | shares
Forfeited, weighted average grant-date price (in dollars per share) | $ / shares
Balance of shares non-vested (in shares) | shares	27,780
Balance of shares non-vested, weighted average grant-date price (in dollars per share) | $ / shares	$ 23.34