Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net income	$ 158	$ 163
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	189	166
Other	(18)	(6)
Other changes in assets and liabilities:
Accounts receivable	(116)	(86)
Gas stored underground	27	68
Derivative assets	30	115
Regulatory assets	35	(32)
Accounts payable	12	(97)
Regulatory liabilities	(14)	(95)
Other	4	(8)
Net cash flows from operating activities	307	188
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(478)	(417)
Other construction and acquisition expenditures	(32)	(34)
Cash receipts on sold receivables	155	173
Proceeds from sale of partial ownership interest in West Riverside	0	25
Other	2	(10)
Net cash flows from (used for) investing activities	(353)	(263)
Cash flows from (used for) financing activities:
Common stock dividends	(123)	(113)
Proceeds from issuance of long-term debt	597	862
Payments to retire long-term debt	(300)	0
Net change in commercial paper and other short-term borrowings	(141)	(532)
Other	(15)	(5)
Net cash flows from (used for) financing activities	18	212
Net increase (decrease) in cash, cash equivalents and restricted cash	(28)	137
Cash, cash equivalents and restricted cash at beginning of period	63	24
Cash, cash equivalents and restricted cash at end of period	35	161
Supplemental cash flows information:
Interest	(97)	(93)
Income taxes, net	(2)	0
Significant non-cash investing and financing activities:
Accrued capital expenditures	204	254
Beneficial interest obtained in exchange for securitized accounts receivable	184	153
IPL [Member]
Cash flows from operating activities:
Net income	63	72
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	96	96
Other	(11)	1
Other changes in assets and liabilities:
Accounts receivable	(119)	(106)
Gas stored underground	18	34
Derivative assets	20	69
Accounts payable	(7)	(56)
Regulatory liabilities	4	(59)
Other	12	(27)
Net cash flows from operating activities	76	24
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(253)	(101)
Cash receipts on sold receivables	155	173
Other	(9)	(2)
Net cash flows from (used for) investing activities	(107)	70
Cash flows from (used for) financing activities:
Common stock dividends	(50)	(70)
Capital contributions from parent	50	0
Other	(10)	(4)
Net cash flows from (used for) financing activities	(10)	(74)
Net increase (decrease) in cash, cash equivalents and restricted cash	(41)	20
Cash, cash equivalents and restricted cash at beginning of period	53	15
Cash, cash equivalents and restricted cash at end of period	12	35
Supplemental cash flows information:
Interest	(32)	(37)
Income taxes, net	(2)	0
Significant non-cash investing and financing activities:
Accrued capital expenditures	110	98
Beneficial interest obtained in exchange for securitized accounts receivable	184	153
WPL [Member]
Cash flows from operating activities:
Net income	92	88
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	90	68
Other	(11)	(12)
Other changes in assets and liabilities:
Gas stored underground	9	35
Derivative assets	12	46
Regulatory assets	29	(37)
Accounts payable	15	(48)
Derivative liabilities	(4)	28
Regulatory liabilities	(18)	(35)
Other	27	52
Net cash flows from operating activities	241	185
Cash flows from (used for) investing activities:
Utility business construction and acquisition expenditures	(225)	(316)
Proceeds from sale of partial ownership interest in West Riverside	0	25
Other	12	(4)
Net cash flows from (used for) investing activities	(213)	(295)
Cash flows from (used for) financing activities:
Common stock dividends	(49)	(46)
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)	(230)
Other	(9)	(10)
Net cash flows from (used for) financing activities	(24)	191
Net increase (decrease) in cash, cash equivalents and restricted cash	4	81
Cash, cash equivalents and restricted cash at beginning of period	7	5
Cash, cash equivalents and restricted cash at end of period	11	86
Supplemental cash flows information:
Interest	(40)	(40)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$ 91	$ 152