Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 703	$ 686	$ 674
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	676	671	657
Deferred tax expense (benefit) and tax credits	14	13	(78)
Equity component of allowance for funds used during construction	(74)	(44)	(18)
Other	35	27	35
Other changes in assets and liabilities:
Accounts receivable	(414)	(672)	(530)
Materials and supplies	(62)	(27)	(13)
Regulatory assets	24	(108)	51
Derivative assets	149	(61)	(142)
Accounts payable	(122)	78	37
Regulatory liabilities	(149)	22	(66)
Derivative liabilities	19	70	(17)
Deferred income taxes	84	4	193
Pension and other benefit obligations	(28)	(97)	(137)
Other	12	(76)	(64)
Net cash flows from operating activities	867	486	582
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(1,731)	(1,392)	(1,070)
Other construction and acquisition expenditures	(123)	(92)	(99)
Cash receipts on sold receivables	453	598	502
Proceeds from sales of partial ownership interests in West Riverside	120	0	0
Other	(120)	(47)	(61)
Net cash flows from (used for) investing activities	(1,401)	(933)	(728)
Cash flows from (used for) financing activities:
Common stock dividends	(456)	(428)	(403)
Proceeds from issuance of common stock, net	246	25	28
Redemption of cumulative preferred stock of IPL	0	0	(200)
Proceeds from issuance of long-term debt	1,455	1,338	600
Payments to retire long-term debt	(508)	(633)	(8)
Net change in commercial paper	(167)	127	126
Other	3	2	(13)
Net cash flows from (used for) financing activities	573	431	130
Net increase (decrease) in cash, cash equivalents and restricted cash	39	(16)	(16)
Cash, cash equivalents and restricted cash at beginning of period	24	40	56
Cash, cash equivalents and restricted cash at end of period	63	24	40
Supplemental cash flows information:
Interest	(378)	(311)	(272)
Income taxes, net	88	(6)	(3)
Significant non-cash investing and financing activities:
Accrued capital expenditures	364	382	141
Beneficial interest obtained in exchange for securitized accounts receivable	216	185	214
Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	98
IPL [Member]
Cash flows from operating activities:
Net income	366	360	365
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	388	381	375
Other	(2)	(21)	(10)
Other changes in assets and liabilities:
Accounts receivable	(437)	(611)	(539)
Materials and supplies	(39)	(13)	(7)
Regulatory assets	58	56	30
Derivative assets	84	(54)	(55)
Accounts payable	(68)	65	15
Regulatory liabilities	(92)	53	1
Derivative liabilities	(16)	42	(8)
Deferred income taxes	36	(24)	62
Pension and other benefit obligations	(11)	(65)	(59)
Other	(6)	(86)	(17)
Net cash flows from operating activities	261	83	153
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(712)	(372)	(384)
Cash receipts on sold receivables	453	598	502
Other	(67)	(11)	(27)
Net cash flows from (used for) investing activities	(326)	215	91
Cash flows from (used for) financing activities:
Common stock dividends	(280)	(321)	(400)
Capital contributions from parent	80	0	50
Redemption of cumulative preferred stock of IPL	0	0	(200)
Proceeds from issuance of long-term debt	296	0	300
Other	7	4	(10)
Net cash flows from (used for) financing activities	103	(317)	(260)
Net increase (decrease) in cash, cash equivalents and restricted cash	38	(19)	(16)
Cash, cash equivalents and restricted cash at beginning of period	15	34	50
Cash, cash equivalents and restricted cash at end of period	53	15	34
Supplemental cash flows information:
Interest	(150)	(148)	(138)
Income taxes, net	117	36	47
Significant non-cash investing and financing activities:
Accrued capital expenditures	140	56	57
Beneficial interest obtained in exchange for securitized accounts receivable	216	185	214
IPL [Member] | Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	76
WPL [Member]
Cash flows from operating activities:
Net income	345	315	268
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	280	283	276
Deferred tax expense (benefit) and tax credits	(13)	4	(79)
Equity component of allowance for funds used during construction	(59)	(36)	(11)
Other	25	21	22
Other changes in assets and liabilities:
Accounts receivable	23	(53)	3
Regulatory assets	(34)	(163)	21
Derivative assets	65	(7)	(87)
Accounts payable	(57)	22	4
Regulatory liabilities	(57)	(31)	(67)
Deferred income taxes	50	32	132
Pension and other benefit obligations	(19)	(19)	(63)
Other	29	(69)	(48)
Net cash flows from operating activities	578	299	371
Cash flows from (used for) investing activities:
Utility construction and acquisition expenditures	(1,019)	(1,020)	(686)
Proceeds from sales of partial ownership interests in West Riverside	120	0	0
Other	(47)	(13)	(30)
Net cash flows from (used for) investing activities	(946)	(1,033)	(716)
Cash flows from (used for) financing activities:
Common stock dividends	(184)	(176)	(168)
Capital contributions from parent	245	530	245
Proceeds from issuance of long-term debt	297	588	300
Payments to retire long-term debt	0	(250)	0
Net change in commercial paper	28	54	(21)
Other	(16)	(9)	(12)
Net cash flows from (used for) financing activities	370	737	344
Net increase (decrease) in cash, cash equivalents and restricted cash	2	3	(1)
Cash, cash equivalents and restricted cash at beginning of period	5	2	3
Cash, cash equivalents and restricted cash at end of period	7	5	2
Supplemental cash flows information:
Interest	(146)	(111)	(101)
Income taxes, net	(50)	(56)	(38)
Significant non-cash investing and financing activities:
Accrued capital expenditures	217	$ 319	$ 81
WPL [Member] | Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	$ 22