Derivative Instruments (Fair Value Of Financial Instruments) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Current derivative assets	$ 217	$ 113
Non-current derivative assets	142	63
Current derivative liabilities	84	8
Non-current derivative liabilities	11	1
IPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	131	48
Non-current derivative assets	76	36
Current derivative liabilities	58	4
Non-current derivative liabilities	9	0
WPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	86	65
Non-current derivative assets	66	27
Current derivative liabilities	26	4
Non-current derivative liabilities	$ 2	$ 1

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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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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- Definition

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