Stock-Based Compensation (Summary of Restricted Stock Transactions) (Details) - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of the restricted stock transactions
Shares, Non-vested and Outstanding, Beginning	128,224	109,176	96,639
Shares, Granted	0	72,985	63,811
Shares, Vested	(62,137)	(51,021)	(49,493)
Shares, Forfeited	(2,332)	(2,916)	(1,781)
Shares, Non-vested and Outstanding, Ending	63,755	128,224	109,176
Weighted Average Grant Date Fair Value, Outstanding Beginning	$ 34.66	$ 40.87	$ 44.85
Weighted Average Grant Date Fair Value, Granted		31.18	37.37
Weighted Average Grant Date Fair Value, Vested	36.50	42.66	43.98
Weighted Average Grant Date Fair Value, Forfeited	33.65	40.30	45.39
Weighted Average Grant Date Fair Value, Outstanding Ending	$ 32.90	$ 34.66	$ 40.87
Weighted average remaining contractual life (in years)	1 year 7 months 6 days