Employee Benefit Plans (Summary of 401k Activity) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense associated with the retirement benefit plan	$ 1,061	$ 1,023	$ 905
Common Stock Shares Held In Benefit Plan	198,300	203,989	229,276