Receivables (Additional Attributes Of Receivables Sold Under The Agreement) (Details) - IPL [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Receivables [Line Items]
Collections	$ 483.7	$ 434.1	$ 1,000.7	$ 935.3
Write-offs, net of recoveries	$ 1.9	$ 2.3	$ 8.0	$ 6.9