Acquisition (Summary of Supplemental Pro Forma Financial Information) (Details) - MNB Corporation [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Net interest income	$ 48,812	$ 46,199
Other income	14,387	11,966
Total net interest income and other income	63,199	58,165
Net income	$ 14,272	$ 16,035
Basic earnings per common share	$ 2.87	$ 3.24
Diluted earnings per common share	$ 2.85	$ 3.21