Income Taxes (Schedule Of Income Tax Provision) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income before provision for income taxes	$ 1,260.9	$ 549.5	$ 855.9
Current provision for income taxes, Federal	217.9	53.8	94.1
Current provision for income taxes, State	38.6	6.6	18.7
Current provision for income taxes	256.5	60.4	112.8
Deferred provision for income taxes, Federal	36.7	57.3	70.7
Deferred provision for income taxes, State	7.9	11.0	14.8
Deferred provision for income taxes	44.6	68.3	85.5
Interest	1.5	(0.2)	1.5
Unrecognized Tax Benefits, Income Tax Penalties Expense	0.0	0.0	0.0
Interest and penalties expense (benefit)	1.5	(0.2)	1.5
Provision for income taxes	$ 302.6	$ 128.5	$ 199.8