Derivative Instruments (Fair Value Of Financial Instruments) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Current derivative assets	$ 44	$ 111
Non-current derivative assets	44	126
Current derivative liabilities	51	59
Non-current derivative liabilities	47	20
IPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	30	69
Non-current derivative assets	24	69
Current derivative liabilities	22	40
Non-current derivative liabilities	8	6
WPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	14	42
Non-current derivative assets	20	57
Current derivative liabilities	29	19
Non-current derivative liabilities	$ 39	$ 14

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483466/210-20-50-3

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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