Income Taxes (Reconciliation Of Effective Tax Rate) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Abstract]
Components of income from continuing operations: United States													$ (111.3)	$ 117.0	$ 308.8
Components of income from continuing operations: Foreign													(2.8)	(9.7)	2.1
(Loss) income from continuing operations before income taxes	2.6		(72.1)		(33.8)		(10.8)		17.8	(0.6)	38.5	51.6	(114.1)	107.3	310.9
Statutory tax rate													35.00%	35.00%	35.00%
Federal income tax (benefit) expense at statutory rate													(39.9)	37.6	108.8
Change in valuation allowance													73.8	3.2	2.0
Foreign tax branch benefit													(5.0)	(3.2)	(2.0)
State income taxes, net of federal benefit													(4.9)	2.1	8.3
Stock-based compensation tax shortfall													1.7	0.9	0.6
Income tax credits													(0.5)	(3.4)	(1.1)
Unrecognized tax benefits													(0.8)	2.5	1.0
US deferred tax on foreign earnings													0.3	(2.0)	0.8
Other, net													0.6	2.5	1.8
Income tax expense	$ 65.9	[1]	$ (25.0)	[1]	$ (12.8)	[1]	$ (2.8)	[1]	$ 5.9	$ (0.9)	$ 15.0	$ 20.2	$ 25.3	$ 40.2	$ 120.2
Effective tax rate													(22.20%)	37.50%	38.70%

[1] The fourth quarter includes an increase to income tax expense of $66.7 million related to a valuation allowance with respect to our U.S. federal deferred tax assets and our remaining state deferred tax assets.