Earnings per Share (Schedule of Earnings per Share, Basic and Diluted) (Details) - $ / shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Weighted Average Number of Shares Outstanding, Basic	65,862	66,179	66,182	66,427
Effect of dilutive stock options and restricted stock units	404	358	491	380
Weighted Average Number of Shares Outstanding, Diluted, Total	66,266	66,537	66,673	66,807
Earnings Per Share, Basic	$ 1.53	$ 0.95	$ 2.98	$ 0.18
Earnings Per Share, Diluted	$ 1.52	$ 0.94	$ 2.96	$ 0.18