Benefit Plans (Carrying Value Of Entity's Deferred Compensation Obligations Interest And Equity Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Carrying value of deferred compensation obligations	$ 18.3	$ 17.8
IPL [Member]
Defined Benefit Plan Disclosure [Line Items]
Carrying value of deferred compensation obligations	$ 5.0	$ 5.2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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