Segments Of Business (Tables)

9 Months Ended

Sep. 30, 2023

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Three Months Ended September 30, 2023
Revenues	$995	$47	$13	$1,055	$22	$1,077
Operating income (loss)	319	(4)	—	315	7	322
Net income (loss) attributable to Alliant Energy common shareowners				277	(18)	259
Three Months Ended September 30, 2022
Revenues	$1,039	$62	$11	$1,112	$23	$1,135
Operating income (loss)	304	(3)	1	302	7	309
Net income (loss) attributable to Alliant Energy common shareowners				245	(18)	227

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Nine Months Ended September 30, 2023
Revenues	$2,562	$400	$38	$3,000	$66	$3,066
Operating income	682	48	12	742	18	760
Net income (loss) attributable to Alliant Energy common shareowners				598	(16)	582
Nine Months Ended September 30, 2022
Revenues	$2,624	$418	$35	$3,077	$70	$3,147
Operating income	680	62	4	746	23	769
Net income attributable to Alliant Energy common shareowners				574	5	579

IPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$551	$31	$12	$594
Operating income (loss)	171	(2)	4	173
Net income				170
Three Months Ended September 30, 2022
Revenues	$596	$33	$11	$640
Operating income (loss)	174	(3)	—	171
Net income				154
Nine Months Ended September 30, 2023
Revenues	$1,370	$224	$36	$1,630
Operating income	342	25	12	379
Net income				331
Nine Months Ended September 30, 2022
Revenues	$1,438	$224	$34	$1,696
Operating income	353	33	3	389
Net income				327

WPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$444	$16	$1	$461
Operating income (loss)	148	(2)	(4)	142
Net income				107
Three Months Ended September 30, 2022
Revenues	$443	$29	$—	$472
Operating income	130	—	1	131
Net income				91
Nine Months Ended September 30, 2023
Revenues	$1,192	$176	$2	$1,370
Operating income	340	23	—	363
Net income				267
Nine Months Ended September 30, 2022
Revenues	$1,186	$194	$1	$1,381
Operating income	327	29	1	357
Net income				247

IPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Three Months Ended September 30, 2023
Revenues	$995	$47	$13	$1,055	$22	$1,077
Operating income (loss)	319	(4)	—	315	7	322
Net income (loss) attributable to Alliant Energy common shareowners				277	(18)	259
Three Months Ended September 30, 2022
Revenues	$1,039	$62	$11	$1,112	$23	$1,135
Operating income (loss)	304	(3)	1	302	7	309
Net income (loss) attributable to Alliant Energy common shareowners				245	(18)	227

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Nine Months Ended September 30, 2023
Revenues	$2,562	$400	$38	$3,000	$66	$3,066
Operating income	682	48	12	742	18	760
Net income (loss) attributable to Alliant Energy common shareowners				598	(16)	582
Nine Months Ended September 30, 2022
Revenues	$2,624	$418	$35	$3,077	$70	$3,147
Operating income	680	62	4	746	23	769
Net income attributable to Alliant Energy common shareowners				574	5	579

IPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$551	$31	$12	$594
Operating income (loss)	171	(2)	4	173
Net income				170
Three Months Ended September 30, 2022
Revenues	$596	$33	$11	$640
Operating income (loss)	174	(3)	—	171
Net income				154
Nine Months Ended September 30, 2023
Revenues	$1,370	$224	$36	$1,630
Operating income	342	25	12	379
Net income				331
Nine Months Ended September 30, 2022
Revenues	$1,438	$224	$34	$1,696
Operating income	353	33	3	389
Net income				327

WPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$444	$16	$1	$461
Operating income (loss)	148	(2)	(4)	142
Net income				107
Three Months Ended September 30, 2022
Revenues	$443	$29	$—	$472
Operating income	130	—	1	131
Net income				91
Nine Months Ended September 30, 2023
Revenues	$1,192	$176	$2	$1,370
Operating income	340	23	—	363
Net income				267
Nine Months Ended September 30, 2022
Revenues	$1,186	$194	$1	$1,381
Operating income	327	29	1	357
Net income				247

WPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Three Months Ended September 30, 2023
Revenues	$995	$47	$13	$1,055	$22	$1,077
Operating income (loss)	319	(4)	—	315	7	322
Net income (loss) attributable to Alliant Energy common shareowners				277	(18)	259
Three Months Ended September 30, 2022
Revenues	$1,039	$62	$11	$1,112	$23	$1,135
Operating income (loss)	304	(3)	1	302	7	309
Net income (loss) attributable to Alliant Energy common shareowners				245	(18)	227

Alliant Energy					ATC Holdings,	Alliant
	Utility				Non-Utility,	Energy
	Electric	Gas	Other	Total	Parent and Other	Consolidated
	(in millions)
Nine Months Ended September 30, 2023
Revenues	$2,562	$400	$38	$3,000	$66	$3,066
Operating income	682	48	12	742	18	760
Net income (loss) attributable to Alliant Energy common shareowners				598	(16)	582
Nine Months Ended September 30, 2022
Revenues	$2,624	$418	$35	$3,077	$70	$3,147
Operating income	680	62	4	746	23	769
Net income attributable to Alliant Energy common shareowners				574	5	579

IPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$551	$31	$12	$594
Operating income (loss)	171	(2)	4	173
Net income				170
Three Months Ended September 30, 2022
Revenues	$596	$33	$11	$640
Operating income (loss)	174	(3)	—	171
Net income				154
Nine Months Ended September 30, 2023
Revenues	$1,370	$224	$36	$1,630
Operating income	342	25	12	379
Net income				331
Nine Months Ended September 30, 2022
Revenues	$1,438	$224	$34	$1,696
Operating income	353	33	3	389
Net income				327

WPL	Electric	Gas	Other	Total
	(in millions)
Three Months Ended September 30, 2023
Revenues	$444	$16	$1	$461
Operating income (loss)	148	(2)	(4)	142
Net income				107
Three Months Ended September 30, 2022
Revenues	$443	$29	$—	$472
Operating income	130	—	1	131
Net income				91
Nine Months Ended September 30, 2023
Revenues	$1,192	$176	$2	$1,370
Operating income	340	23	—	363
Net income				267
Nine Months Ended September 30, 2022
Revenues	$1,186	$194	$1	$1,381
Operating income	327	29	1	357
Net income				247