Benefit Plans (Defined Benefit Pension And Other Postretirement Benefits Plans) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 2	$ 7	$ 8
Interest cost	9	9	27	26
Expected return on plan assets	(18)	(17)	(52)	(51)
Amortization of prior service credit	0	(1)	0	(1)
Amortization of actuarial loss	8	10	24	29
Total	2	3	6	11
OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	2	3
Interest cost	1	1	4	3
Expected return on plan assets	0	(1)	(3)	(3)
Amortization of prior service credit	0	0	0	0
Amortization of actuarial loss	1	1	2	3
Total	2	2	5	6
IPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	4	5
Interest cost	4	4	12	12
Expected return on plan assets	(7)	(8)	(23)	(24)
Amortization of actuarial loss	3	5	10	13
Total	1	2	3	6
IPL [Member] | OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	1	1
Interest cost	1	1	2	2
Expected return on plan assets	(1)	(1)	(3)	(3)
Amortization of actuarial loss	0	0	0	1
Total	0	0	0	1
WPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	2	3
Interest cost	4	3	12	11
Expected return on plan assets	(7)	(8)	(23)	(23)
Amortization of actuarial loss	4	5	12	14
Total	1	1	3	5
WPL [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	0	0	0	0
Amortization of actuarial loss	0	1	1	2
Total	$ 1	$ 2	$ 3	$ 4