Benefit Plans (Amounts Recognized On The Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Amounts recognized on the balance sheets consist of:
Pension and other benefit obligations	$ (277)	$ (374)
Pension Plans, Defined Benefit [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	0	0
Current liabilities	(2)	(2)
Pension and other benefit obligations	(167)	(238)
Net amounts recognized at December 31	(169)	(240)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	376	429
Prior service credit	(3)	(4)
Net amount recognized at December 31	373	425
Other Postretirement Benefits Plans [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	9	13
Current liabilities	(8)	(8)
Pension and other benefit obligations	(86)	(109)
Net amounts recognized at December 31	(85)	(104)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	20	38
Prior service credit	0	(1)
Net amount recognized at December 31	20	37
IPL [Member]
Amounts recognized on the balance sheets consist of:
Pension and other benefit obligations	(62)	(127)
IPL [Member] | Pension Plans, Defined Benefit [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	0	0
Current liabilities	0	0
Pension and other benefit obligations	(45)	(105)
Net amounts recognized at December 31	(45)	(105)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	154	180
Prior service credit	(1)	(1)
Net amount recognized at December 31	153	179
IPL [Member] | Other Postretirement Benefits Plans [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	6	10
Current liabilities	(2)	(2)
Pension and other benefit obligations	(14)	(18)
Net amounts recognized at December 31	(10)	(10)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	14	13
Prior service credit	0	0
Net amount recognized at December 31	14	13
WPL [Member]
Amounts recognized on the balance sheets consist of:
Pension and other benefit obligations	(140)	(159)
WPL [Member] | Pension Plans, Defined Benefit [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	0	0
Current liabilities	0	0
Pension and other benefit obligations	(90)	(96)
Net amounts recognized at December 31	(90)	(96)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	165	188
Prior service credit	0	(1)
Net amount recognized at December 31	165	187
WPL [Member] | Other Postretirement Benefits Plans [Member]
Amounts recognized on the balance sheets consist of:
Non-current assets	3	3
Current liabilities	(5)	(6)
Pension and other benefit obligations	(49)	(61)
Net amounts recognized at December 31	(51)	(64)
Amounts recognized in Regulatory Assets consist of:
Net actuarial loss	6	18
Prior service credit	0	(1)
Net amount recognized at December 31	$ 6	$ 17