Note 9 - Per Share Data - Antidilutive Securities Excluded from Computation (Details) - shares		3 Months Ended	6 Months Ended
		Jun. 30, 2022	Jun. 30, 2022	Jun. 30, 2021
Antidilutive securities (in shares)		51,930	53,353
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)			123,667	154,617
Restricted Stock Units (Stock Settled) [Member]
Antidilutive securities (in shares)	[1]		166,683	165,309

[1] For the three months ended March 31, 2022, this includes 54,792 units which are expected to settle in cash.