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Discontinued Operations And Assets And Liabilities Held For Sale (Components Of Discontinued Operations In Condensed Consolidated Statements Of Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating revenues	$ 0	$ 93.9	$ 0.9	$ 148.5
Operating expenses	0.9	93.0	6.5	154.9
Interest expense and other	0	0.2	0	0.2
Income (loss) before income taxes	(0.9)	0.7	(5.6)	(6.6)
Income tax expense (benefit)	(0.3)	0.3	(2.0)	(2.6)
Income (loss) from discontinued operations, net of tax	$ (0.6)	$ 0.4	$ (3.6)	$ (4.0)

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- Definition

Amount of interest expense and other attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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