Derivative Instruments (Fair Value Of Financial Instruments) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Current derivative assets	$ 86	$ 111
Non-current derivative assets	61	126
Current derivative liabilities	54	59
Non-current derivative liabilities	43	20
IPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	61	69
Non-current derivative assets	34	69
Current derivative liabilities	27	40
Non-current derivative liabilities	10	6
WPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	25	42
Non-current derivative assets	27	57
Current derivative liabilities	27	19
Non-current derivative liabilities	$ 33	$ 14