Shareholders' Equity (Common Stock Issued With The Exercise Of Stock Options) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stockholders' Equity Note [Abstract]
Shares issued (in shares)	0	90,248	55,000	101,475
Proceeds from the exercise of stock options	$ 0.0	$ 2.9	$ 1.0	$ 3.2
Average exercise price per share (in dollars per share)	$ 0	$ 31.76	$ 18.12	$ 31.11