Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from (used for) operating activities:
Net income	$ 686	$ 674	$ 624
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortization	671	657	615
Deferred tax expense (benefit) and tax credits	13	(78)	(66)
Other	(18)	17	(2)
Other changes in assets and liabilities:
Accounts receivable	(672)	(530)	(468)
Regulatory assets	(108)	51	(130)
Derivative assets	(61)	(142)	(7)
Accounts payable	78	37	(3)
Regulatory liabilities	22	(66)	(113)
Derivative liabilities	70	(17)	(12)
Deferred income taxes	4	193	171
Pension and other benefit obligations	(97)	(137)	27
DAEC PPA amendment buyout payment	0	0	(110)
Other	(102)	(77)	(25)
Net cash flows from (used for) operating activities	486	582	501
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(1,392)	(1,070)	(1,293)
Other construction and acquisition expenditures	(92)	(99)	(73)
Cash receipts on sold receivables	598	502	458
Other	(47)	(61)	(43)
Net cash flows from (used for) investing activities	(933)	(728)	(951)
Cash flows from (used for) financing activities:
Common stock dividends	(428)	(403)	(377)
Proceeds from issuance of common stock, net	25	28	247
Payments to redeem cumulative preferred stock of IPL	0	(200)	0
Proceeds from issuance of long-term debt	1,338	600	1,250
Payments to retire long-term debt	(633)	(8)	(657)
Net change in commercial paper	127	126	52
Contributions from noncontrolling interest	29	0	0
Distributions to noncontrolling interest	(29)	0	0
Other	2	(13)	(27)
Net cash flows from (used for) financing activities	431	130	488
Net increase (decrease) in cash, cash equivalents and restricted cash	(16)	(16)	38
Cash, cash equivalents and restricted cash at beginning of period	40	56	18
Cash, cash equivalents and restricted cash at end of period	24	40	56
Supplemental cash flows information:
Interest	(311)	(272)	(274)
Income taxes, net	(6)	(3)	5
Significant non-cash investing and financing activities:
Accrued capital expenditures	382	141	131
Beneficial interest obtained in exchange for securitized accounts receivable	185	214	188
IPL [Member]
Cash flows from (used for) operating activities:
Net income	360	365	334
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortization	381	375	356
Deferred tax expense (benefit) and tax credits	(13)	(14)	(52)
Equity component of allowance for funds used during construction	(8)	(7)	(17)
Other	0	11	12
Other changes in assets and liabilities:
Accounts receivable	(611)	(539)	(466)
Regulatory assets	56	30	(93)
Derivative assets	(54)	(55)	(7)
Gas stored underground	(20)	(20)	2
Accounts payable	65	15	6
Regulatory liabilities	53	1	(20)
Derivative liabilities	42	(8)	(5)
Deferred income taxes	(24)	62	79
Pension and other benefit obligations	(65)	(59)	18
DAEC PPA amendment buyout payment	0	0	(110)
Other	(79)	(4)	(43)
Net cash flows from (used for) operating activities	83	153	(6)
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(372)	(384)	(687)
Cash receipts on sold receivables	598	502	458
Other	(11)	(27)	(72)
Net cash flows from (used for) investing activities	215	91	(301)
Cash flows from (used for) financing activities:
Common stock dividends	(321)	(400)	(236)
Capital contributions from parent	0	50	404
Payments to redeem cumulative preferred stock of IPL	0	(200)	0
Proceeds from issuance of long-term debt	0	300	400
Payments to retire long-term debt	0	0	(200)
Other	4	(10)	(20)
Net cash flows from (used for) financing activities	(317)	(260)	348
Net increase (decrease) in cash, cash equivalents and restricted cash	(19)	(16)	41
Cash, cash equivalents and restricted cash at beginning of period	34	50	9
Cash, cash equivalents and restricted cash at end of period	15	34	50
Supplemental cash flows information:
Interest	(148)	(138)	(141)
Income taxes, net	36	47	(18)
Significant non-cash investing and financing activities:
Accrued capital expenditures	56	57	73
Beneficial interest obtained in exchange for securitized accounts receivable	185	214	188
WPL [Member]
Cash flows from (used for) operating activities:
Net income	315	268	249
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortization	283	276	254
Deferred tax expense (benefit) and tax credits	4	(79)	(15)
Other	(15)	11	2
Other changes in assets and liabilities:
Accounts receivable	(53)	3	(1)
Regulatory assets	(163)	21	(37)
Derivative assets	(7)	(87)	0
Regulatory liabilities	(31)	(67)	(93)
Deferred income taxes	32	132	90
Pension and other benefit obligations	(19)	(63)	11
Other	(47)	(44)	6
Net cash flows from (used for) operating activities	299	371	466
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(1,020)	(686)	(606)
Other	(13)	(30)	(7)
Net cash flows from (used for) investing activities	(1,033)	(716)	(613)
Cash flows from (used for) financing activities:
Common stock dividends	(176)	(168)	(160)
Capital contributions from parent	530	245	25
Proceeds from issuance of long-term debt	588	300	350
Payments to retire long-term debt	(250)	0	(150)
Net change in commercial paper	54	(21)	89
Contributions from noncontrolling interest	29	0	0
Distributions to noncontrolling interest	(29)	0	0
Other	(9)	(12)	(8)
Net cash flows from (used for) financing activities	737	344	146
Net increase (decrease) in cash, cash equivalents and restricted cash	3	(1)	(1)
Cash, cash equivalents and restricted cash at beginning of period	2	3	4
Cash, cash equivalents and restricted cash at end of period	5	2	3
Supplemental cash flows information:
Interest	(111)	(101)	(102)
Income taxes, net	(56)	(38)	13
Significant non-cash investing and financing activities:
Accrued capital expenditures	$ 319	$ 81	$ 55