Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Components of Deferred Tax Assets and Liabilities [Abstract]
Pension	$ 47.2	$ 38.7
Operating lease liabilities	31.3	30.6
Postretirement benefits	20.8	19.6
Inventory	12.3	14.9
Other deferred tax assets	5.2	5.0
Payroll accruals	7.6	2.9
Bad debt reserves	0.8	1.0
Subtotal	125.2	112.7
less: valuation allowances	(0.6)	(0.4)
Deferred tax assets	124.6	112.3
Fixed assets	(34.5)	(32.2)
Operating lease right-of-use assets	(29.1)	(28.7)
Other deferred tax liabilities	(4.9)	(4.5)
Computer software	(2.4)	(2.9)
Deferred tax liabilities	(70.9)	(68.3)
Net deferred tax assets	53.7	44.0
Deferred Tax Assets, Net, Classification [Abstract]
Net deferred tax assets	53.7	44.0
Other Noncurrent Assets [Member]
Deferred Tax Assets, Net, Classification [Abstract]
Deferred tax assets, included in other non-current assets	54.1	44.5
Other Noncurrent Liabilities [Member]
Deferred Tax Assets, Net, Classification [Abstract]
Deferred tax liabilities included in other non-current liabilities	$ (0.4)	$ (0.5)