Stock-Based Compensation (Components Of Stock-Based Compensation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 33.0	$ 35.5	$ 36.6
Recognized tax benefits on stock-based compensation expense	10.3	9.0	17.2
To Be Settled With Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	19.9	21.5	20.3
Employee contributions for above stock plans	13.1	14.0	16.3
Total stock-based compensation	33.0	35.5	36.6
Recognized tax benefits on stock-based compensation expense	4.7	5.1	7.3
To Be Settled With Stock \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	3.7	5.6	5.5
To Be Settled With Stock \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2.1	1.9	2.1
To Be Settled With Stock \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1.3	1.3	1.4
To Be Settled With Stock \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1.0	1.1	1.1
To Be Settled With Stock \| Performance Stock Unit Awards - TSR Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2.8	1.2	0.0
To Be Settled With Stock \| Performance Stock Unit Awards - EBIT CAGR Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	3.8	2.9	0.0
To Be Settled With Stock \| Performance Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1.8	3.6	5.4
To Be Settled With Stock \| Profitable Growth Incentive (PGI) awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.9	1.4
To Be Settled With Stock \| Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2.0	2.1	2.5
To Be Settled With Stock \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1.4	0.9	0.9
To Be Settled In Cash
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	11.0	3.9	1.2
To Be Settled In Cash \| Stock-based retirement plans contributions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.6	1.0	1.2
To Be Settled In Cash \| Deferred Stock Compensation Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.0	0.0
To Be Settled In Cash \| Stock-based retirement plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.0	0.0
To Be Settled In Cash \| Discount Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.0	0.0
To Be Settled In Cash \| Performance Stock Unit Awards - TSR Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	4.1	0.8	0.0
To Be Settled In Cash \| Performance Stock Unit Awards - EBIT CAGR Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	5.3	2.5	0.0
To Be Settled In Cash \| Performance Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1.0	(1.3)	(1.4)
To Be Settled In Cash \| Profitable Growth Incentive (PGI) awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.9	1.4
To Be Settled In Cash \| Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.0	0.0
To Be Settled In Cash \| Other, primarily non-employee directors restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	0.0	0.0	0.0
Accounting Standards Update 2016-09 \| To Be Settled With Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized tax benefits on stock-based compensation expense	$ 5.6	$ 3.9	$ 9.9

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