Segments Of Business (Schedule Of Segment Of Business) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Revenues	$ 4,205	$ 3,669	$ 3,416
Depreciation and amortization	671	657	615
Operating income (loss)	928	795	740
Interest expense	325	277	275
Equity income from unconsolidated investments, net	(51)	(62)	(61)
Income tax expense (benefit)	22	(74)	(57)
Net income attributable to common shareowners	686	659	614
Total assets	20,163	18,553	17,710
Investments in equity method subsidiaries	542	508	476
Construction and acquisition expenditures	1,484	1,169	1,366
IPL [Member]
Segment Reporting Information [Line Items]
Revenues	2,256	2,063	1,947
Operating income (loss)	453	460	410
Interest expense	148	139	139
Income tax expense (benefit)	(50)	(36)	(47)
Net income attributable to common shareowners	360	350	324
Total assets	10,075	9,996
WPL [Member]
Segment Reporting Information [Line Items]
Revenues	1,856	1,523	1,395
Operating income (loss)	452	308	306
Interest expense	121	105	104
Income tax expense (benefit)	66	(51)	(19)
Total assets	8,987	7,518
Electric [Member]
Segment Reporting Information [Line Items]
Revenues	3,421	3,081	2,920
Depreciation and amortization	601	591	556
Operating income (loss)	805	716	643
Equity income from unconsolidated investments, net	(1)	(2)	(2)
Total assets	16,571	14,924	14,358
Investments in equity method subsidiaries	20	17	11
Construction and acquisition expenditures	1,318	980	1,109
Electric [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	1,859	1,752	1,695
Depreciation and amortization	342	338	321
Operating income (loss)	397	420	358
Total assets	8,686	8,602	8,518
Construction and acquisition expenditures	336	342	626
Electric [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	1,562	1,329	1,225
Depreciation and amortization	259	253	235
Operating income (loss)	408	296	285
Total assets	7,885	6,322	5,840
Construction and acquisition expenditures	982	638	483
Gas [Member]
Segment Reporting Information [Line Items]
Revenues	642	456	373
Depreciation and amortization	56	54	49
Operating income (loss)	97	63	74
Equity income from unconsolidated investments, net	0	0	0
Total assets	1,631	1,487	1,413
Investments in equity method subsidiaries	0	0	0
Construction and acquisition expenditures	74	90	182
Gas [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	351	265	208
Depreciation and amortization	32	31	30
Operating income (loss)	53	43	50
Total assets	872	819	766
Construction and acquisition expenditures	36	42	59
Gas [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	291	191	165
Depreciation and amortization	24	23	19
Operating income (loss)	44	20	24
Total assets	759	668	647
Construction and acquisition expenditures	38	48	123
Other Utility [Member]
Segment Reporting Information [Line Items]
Revenues	49	49	49
Depreciation and amortization	7	6	5
Operating income (loss)	3	(11)	(1)
Equity income from unconsolidated investments, net	0	0	0
Total assets	860	1,103	990
Investments in equity method subsidiaries	0	0	0
Construction and acquisition expenditures	0	0	2
Other Utility [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	46	46	44
Depreciation and amortization	7	6	5
Operating income (loss)	3	(3)	2
Total assets	517	575	565
Construction and acquisition expenditures	0	0	2
Other Utility [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	3	3	5
Depreciation and amortization	0	0	0
Operating income (loss)	0	(8)	(3)
Total assets	343	528	425
Construction and acquisition expenditures	0	0	0
Utility Business [Member]
Segment Reporting Information [Line Items]
Revenues	4,112	3,586	3,342
Depreciation and amortization	664	651	610
Operating income (loss)	905	768	716
Interest expense	269	244	243
Equity income from unconsolidated investments, net	(1)	(2)	(2)
Income tax expense (benefit)	16	(87)	(66)
Net income attributable to common shareowners	675	618	573
Total assets	19,062	17,514	16,761
Investments in equity method subsidiaries	20	17	11
Construction and acquisition expenditures	1,392	1,070	1,293
Utility Business [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	2,256	2,063	1,947
Depreciation and amortization	381	375	356
Operating income (loss)	453	460	410
Interest expense	148	139	139
Income tax expense (benefit)	(50)	(36)	(47)
Net income attributable to common shareowners	360	350	324
Total assets	10,075	9,996	9,849
Construction and acquisition expenditures	372	384	687
Utility Business [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	1,856	1,523	1,395
Depreciation and amortization	283	276	254
Operating income (loss)	452	308	306
Interest expense	121	105	104
Income tax expense (benefit)	66	(51)	(19)
Net income attributable to common shareowners	315	268	249
Total assets	8,987	7,518	6,912
Construction and acquisition expenditures	1,020	686	606
Non-Utility [Member]
Segment Reporting Information [Line Items]
Revenues	93	83	74
Depreciation and amortization	7	6	5
Operating income (loss)	23	27	24
Interest expense	56	33	32
Equity income from unconsolidated investments, net	(50)	(60)	(59)
Income tax expense (benefit)	6	13	9
Net income attributable to common shareowners	11	41	41
Total assets	1,101	1,039	949
Investments in equity method subsidiaries	522	491	465
Construction and acquisition expenditures	$ 92	$ 99	$ 73