Note 11 - Benefit Plans - Restricted Stock (Details) - Restricted Stock [Member]	9 Months Ended
	Sep. 30, 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	18,713
Granted, weighted average grant-date price (in dollars per share) | $ / shares	$ 21.48
Vested (in shares) | shares	(11,464)
Vested, weighted average grant-date price (in dollars per share) | $ / shares	$ 22.13
Forfeited (in shares) | shares	(5,090)
Forfeited, weighted average grant-date price (in dollars per share) | $ / shares	$ 22.37
Balance of shares non-vested (in shares) | shares	26,537
Balance of shares non-vested, weighted average grant-date price (in dollars per share) | $ / shares	$ 22.20