Common Stock and Earnings per Share (Schedule of Calculations of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic
Net income	$ 6,371	$ 8,186	$ 7,684	$ 8,163	$ 7,057	$ 7,610	$ 7,509	$ 8,092	$ 30,404	$ 30,268	$ 25,014
Weighted average common shares outstanding (in shares)									14,434,445	14,675,136	14,700,558
Basic earnings per share (in dollars per share)	$ 0.44	$ 0.57	$ 0.53	$ 0.56	$ 0.48	$ 0.52	$ 0.51	$ 0.55	$ 2.11	$ 2.06	$ 1.70
Diluted
Net income	$ 6,371	$ 8,186	$ 7,684	$ 8,163	$ 7,057	$ 7,610	$ 7,509	$ 8,092	$ 30,404	$ 30,268	$ 25,014
Weighted average common shares outstanding (in shares)									14,434,445	14,675,136	14,700,558
Effect of dilutive restricted stock, performance based restricted stock ("PBRS"), and SARs									257,480	239,066	215,332
Weighted average common shares outstanding assuming dilution (in shares)									14,691,925	14,914,202	14,915,890
Diluted earnings per share (in dollars per share)	$ 0.43	$ 0.56	$ 0.52	$ 0.55	$ 0.47	$ 0.51	$ 0.50	$ 0.54	$ 2.07	$ 2.03	$ 1.68