Revenues (Tables)

12 Months Ended

Dec. 31, 2020

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy			IPL			WPL
	2020	2019	2018	2020	2019	2018	2020	2019	2018
Electric Utility:
Retail - residential	$1,093	$1,092	$1,063	$602	$601	$590	$491	$491	$473
Retail - commercial	718	770	736	474	510	487	244	260	249
Retail - industrial	841	889	889	488	504	501	353	385	388
Wholesale	168	177	188	57	64	71	111	113	117
Bulk power and other	100	136	124	74	102	82	26	34	42
Total Electric Utility	2,920	3,064	3,000	1,695	1,781	1,731	1,225	1,283	1,269
Gas Utility:
Retail - residential	214	259	254	116	149	152	98	110	102
Retail - commercial	107	133	133	59	75	76	48	58	57
Retail - industrial	12	16	15	8	12	10	4	4	5
Transportation/other	40	47	45	25	28	28	15	19	17
Total Gas Utility	373	455	447	208	264	266	165	191	181
Other Utility:
Steam	36	37	35	36	37	35	—	—	—
Other utility	13	9	13	8	7	10	5	2	3
Total Other Utility	49	46	48	44	44	45	5	2	3
Non-Utility and Other:
Travero and other	74	83	39	—	—	—	—	—	—
Total Non-Utility and Other	74	83	39	—	—	—	—	—	—
Total revenues	$3,416	$3,648	$3,534	$1,947	$2,089	$2,042	$1,395	$1,476	$1,453

IPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy			IPL			WPL
	2020	2019	2018	2020	2019	2018	2020	2019	2018
Electric Utility:
Retail - residential	$1,093	$1,092	$1,063	$602	$601	$590	$491	$491	$473
Retail - commercial	718	770	736	474	510	487	244	260	249
Retail - industrial	841	889	889	488	504	501	353	385	388
Wholesale	168	177	188	57	64	71	111	113	117
Bulk power and other	100	136	124	74	102	82	26	34	42
Total Electric Utility	2,920	3,064	3,000	1,695	1,781	1,731	1,225	1,283	1,269
Gas Utility:
Retail - residential	214	259	254	116	149	152	98	110	102
Retail - commercial	107	133	133	59	75	76	48	58	57
Retail - industrial	12	16	15	8	12	10	4	4	5
Transportation/other	40	47	45	25	28	28	15	19	17
Total Gas Utility	373	455	447	208	264	266	165	191	181
Other Utility:
Steam	36	37	35	36	37	35	—	—	—
Other utility	13	9	13	8	7	10	5	2	3
Total Other Utility	49	46	48	44	44	45	5	2	3
Non-Utility and Other:
Travero and other	74	83	39	—	—	—	—	—	—
Total Non-Utility and Other	74	83	39	—	—	—	—	—	—
Total revenues	$3,416	$3,648	$3,534	$1,947	$2,089	$2,042	$1,395	$1,476	$1,453

WPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenues

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy			IPL			WPL
	2020	2019	2018	2020	2019	2018	2020	2019	2018
Electric Utility:
Retail - residential	$1,093	$1,092	$1,063	$602	$601	$590	$491	$491	$473
Retail - commercial	718	770	736	474	510	487	244	260	249
Retail - industrial	841	889	889	488	504	501	353	385	388
Wholesale	168	177	188	57	64	71	111	113	117
Bulk power and other	100	136	124	74	102	82	26	34	42
Total Electric Utility	2,920	3,064	3,000	1,695	1,781	1,731	1,225	1,283	1,269
Gas Utility:
Retail - residential	214	259	254	116	149	152	98	110	102
Retail - commercial	107	133	133	59	75	76	48	58	57
Retail - industrial	12	16	15	8	12	10	4	4	5
Transportation/other	40	47	45	25	28	28	15	19	17
Total Gas Utility	373	455	447	208	264	266	165	191	181
Other Utility:
Steam	36	37	35	36	37	35	—	—	—
Other utility	13	9	13	8	7	10	5	2	3
Total Other Utility	49	46	48	44	44	45	5	2	3
Non-Utility and Other:
Travero and other	74	83	39	—	—	—	—	—	—
Total Non-Utility and Other	74	83	39	—	—	—	—	—	—
Total revenues	$3,416	$3,648	$3,534	$1,947	$2,089	$2,042	$1,395	$1,476	$1,453