Benefit Plans (Defined Benefit Pension And Other Postretirement Benefits Plans) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 2	$ 2	$ 4
Interest cost	12	9	23	18
Expected return on plan assets	(13)	(17)	(26)	(34)
Amortization of actuarial loss	7	8	14	16
Total	7	2	13	4
OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	1	2
Interest cost	2	2	4	3
Expected return on plan assets	(1)	(2)	(2)	(3)
Amortization of actuarial loss	1	0	1	1
Total	2	1	4	3
IPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	3
Interest cost	5	4	10	8
Expected return on plan assets	(6)	(8)	(13)	(16)
Amortization of actuarial loss	3	4	6	7
Total	3	1	5	2
IPL [Member] | OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	0	1
Interest cost	1	0	2	1
Expected return on plan assets	(1)	(1)	(2)	(2)
Amortization of actuarial loss	1	0	1	0
Total	1	0	1	0
WPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	1	2
Interest cost	5	4	10	8
Expected return on plan assets	(6)	(8)	(11)	(16)
Amortization of actuarial loss	4	4	7	8
Total	4	1	7	2
WPL [Member] | OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	1	0	2	1
Expected return on plan assets	0	0	0	0
Amortization of actuarial loss	0	1	0	1
Total	$ 1	$ 1	$ 2	$ 2