Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities:
Net income	$ 245	$ 323
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	376	333
Deferred tax expense (benefit) and tax credits	(47)	0
Asset valuation charge for IPL's Lansing Generating Station	60	0
Other	(4)	(18)
Other changes in assets and liabilities:
Accounts receivable	(242)	(186)
Gas stored underground	27	63
Derivative assets	(17)	86
Regulatory assets	43	(36)
Accounts payable	75	(84)
Regulatory liabilities	(12)	(116)
Deferred income taxes	86	24
Other	(28)	(78)
Net cash flows from operating activities	562	311
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(870)	(758)
Other construction and acquisition expenditures	(90)	(62)
Cash receipts on sold receivables	306	272
Proceeds from sales of partial ownership interests in West Riverside	123	120
Other	(2)	(54)
Net cash flows from (used for) investing activities	(533)	(482)
Cash flows from (used for) financing activities:
Common stock dividends	(246)	(226)
Proceeds from issuance of common stock, net	12	76
Proceeds from issuance of long-term debt	969	862
Payments to retire long-term debt	(305)	(404)
Net change in commercial paper and other short-term borrowings	(423)	(146)
Other	(6)	(1)
Net cash flows from (used for) financing activities	1	161
Net increase (decrease) in cash, cash equivalents and restricted cash	30	(10)
Cash, cash equivalents and restricted cash at beginning of period	63	24
Cash, cash equivalents and restricted cash at end of period	93	14
Supplemental cash flows information:
Interest	(207)	(179)
Income taxes, net	89	3
Significant non-cash investing and financing activities:
Accrued capital expenditures	272	300
Beneficial interest obtained in exchange for securitized accounts receivable	171	175
Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	99
IPL [Member]
Cash flows from operating activities:
Net income	81	161
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	193	191
Deferred tax expense (benefit) and tax credits	(35)	5
Asset valuation charge for IPL's Lansing Generating Station	60	0
Other	7	(3)
Other changes in assets and liabilities:
Accounts receivable	(251)	(216)
Gas stored underground	17	33
Derivative assets	(18)	43
Accounts payable	19	(32)
Regulatory liabilities	(16)	(78)
Deferred income taxes	92	8
Other	(2)	(60)
Net cash flows from operating activities	147	52
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(500)	(251)
Cash receipts on sold receivables	306	272
Other	(15)	(36)
Net cash flows from (used for) investing activities	(209)	(15)
Cash flows from (used for) financing activities:
Common stock dividends	(100)	(140)
Capital contributions from parent	125	40
Net change in commercial paper and other short-term borrowings	0	55
Other	(7)	2
Net cash flows from (used for) financing activities	18	(43)
Net increase (decrease) in cash, cash equivalents and restricted cash	(44)	(6)
Cash, cash equivalents and restricted cash at beginning of period	53	15
Cash, cash equivalents and restricted cash at end of period	9	9
Supplemental cash flows information:
Interest	(85)	(74)
Income taxes, net	92	25
Significant non-cash investing and financing activities:
Accrued capital expenditures	119	95
Beneficial interest obtained in exchange for securitized accounts receivable	171	175
IPL [Member] | Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	71
WPL [Member]
Cash flows from operating activities:
Net income	156	160
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	178	137
Other	(24)	(30)
Other changes in assets and liabilities:
Accounts receivable	10	33
Gas stored underground	10	31
Derivative assets	3	47
Regulatory assets	44	(35)
Accounts payable	41	(54)
Regulatory liabilities	5	(38)
Other	(32)	17
Net cash flows from operating activities	391	268
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(370)	(507)
Proceeds from sales of partial ownership interests in West Riverside	123	120
Other	0	(15)
Net cash flows from (used for) investing activities	(247)	(402)
Cash flows from (used for) financing activities:
Common stock dividends	(98)	(92)
Capital contributions from parent	55	180
Proceeds from issuance of long-term debt	297	297
Net change in commercial paper and other short-term borrowings	(318)	(246)
Other	(7)	(7)
Net cash flows from (used for) financing activities	(71)	132
Net increase (decrease) in cash, cash equivalents and restricted cash	73	(2)
Cash, cash equivalents and restricted cash at beginning of period	7	5
Cash, cash equivalents and restricted cash at end of period	80	3
Supplemental cash flows information:
Interest	(76)	(69)
Income taxes, net	(10)	(42)
Significant non-cash investing and financing activities:
Accrued capital expenditures	146	$ 196
WPL [Member] | Indemnification Agreement [Member] | Renewable Tax Credits Transferred [Member]
Supplemental cash flows information:
Proceeds from renewable tax credits transferred to other corporate taxpayers	$ 28