Note 14 - Employee Benefits - Activities Under All Plans (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Weighted average exercise price (in dollars per share)	$ 11.21
Granted (in shares)	0	0
Shares available for grant (in shares)	332,005
Restricted Stock [Member]
Unvested restricted shares outstanding (in shares)	19,054
Share-Based Payment Arrangement, Option [Member]
Options outstanding (in shares)	34,229
The 2009 Plan [Member]
Shares available for grant (in shares)	0	0
Weighted average exercise price (in dollars per share)	$ 11.21	$ 11.21	$ 11.21
Shares available for grant (in shares)	0	0	0
The 2009 Plan [Member] | Restricted Stock [Member]
Unvested restricted shares outstanding (in shares)	0	0
Unvested restricted shares outstanding (in shares)	0	0	0
The 2009 Plan [Member] | Share-Based Payment Arrangement, Option [Member]
Options outstanding (in shares)		34,229	34,229
Options outstanding (in shares)	34,229		34,229
The 2017 Plan [Member]
Shares available for grant (in shares)	345,907	365,742
Vested (in shares)	0	0
Shares available for grant (in shares)	332,005	345,907	365,742
Options outstanding (in shares)	0
The 2017 Plan [Member] | Granted January 28, 2020 [Member]
Granted (in shares)		(16,685)
Granted, vesting period (Year)		3 years
The 2017 Plan [Member] | Granted April 23, 2020 [Member]
Granted (in shares)		(3,150)
Granted, vesting period (Year)		1 year
The 2017 Plan [Member] | Granted February 1, 2022 [Member]
Granted (in shares)	(11,286)
Granted, vesting period (Year)	3 years
The 2017 Plan [Member] | Granted April 28, 2020 [Member]
Granted (in shares)	(2,616)
Granted, vesting period (Year)	1 year
The 2017 Plan [Member] | Restricted Stock [Member]
Unvested restricted shares outstanding (in shares)	22,841	21,484
Vested (in shares)	(13,055)	(11,866)
Unvested restricted shares outstanding (in shares)	19,054	22,841	21,484
The 2017 Plan [Member] | Restricted Stock [Member] | Granted January 28, 2020 [Member]
Granted (in shares)		11,123
The 2017 Plan [Member] | Restricted Stock [Member] | Granted April 23, 2020 [Member]
Granted (in shares)		2,100
The 2017 Plan [Member] | Restricted Stock [Member] | Granted February 1, 2022 [Member]
Granted (in shares)	7,524
The 2017 Plan [Member] | Restricted Stock [Member] | Granted April 28, 2020 [Member]
Granted (in shares)	1,744
The 2017 Plan [Member] | Share-Based Payment Arrangement, Option [Member]
Options outstanding (in shares)		0	0
Vested (in shares)	0		0
Options outstanding (in shares)	0		0
The 2017 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Granted January 28, 2020 [Member]
Granted (in shares)			0
The 2017 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Granted April 23, 2020 [Member]
Granted (in shares)			0
The 2017 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Granted February 1, 2022 [Member]
Granted (in shares)	0
The 2017 Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Granted April 28, 2020 [Member]
Granted (in shares)	0