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Segments Of Business | 9 Months Ended
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Sep. 30, 2020
Segment Reporting Information [Line Items] |
Segments Of Business | 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, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $852 |  |  |  | $42 |  |  |  | $10 |  |  |  | $904 |  |  |  | $16 |  |  |  | $920 |
Operating income (loss) | 251 |  |  | (1 | ) |  | 1 |  |  | 251 |  |  | 21 |  |  | 272 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 221 |  |  | 25 |  |  | 246 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $916 |  |  |  | $42 |  |  |  | $11 |  |  |  | $969 |  |  |  | $21 |  |  |  | $990 |
Operating income (loss) | 284 |  |  | (5 | ) |  | 3 |  |  | 282 |  |  | 8 |  |  | 290 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 217 |  |  | 9 |  |  | 226 |
Alliant Energy |  |  |  |  |  |  |  |  | ATC Holdings, |  | Alliant
| Utility |  | Non-Utility, |  | Energy
| Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
| (in millions)
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,257 |  |  |  | $253 |  |  |  | $32 |  |  |  | $2,542 |  |  |  | $57 |  |  |  | $2,599 |
Operating income | 549 |  |  | 48 |  |  | 5 |  |  | 602 |  |  | 26 |  |  | 628 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 510 |  |  | 40 |  |  | 550 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,350 |  |  |  | $323 |  |  |  | $33 |  |  |  | $2,706 |  |  |  | $62 |  |  |  | $2,768 |
Operating income | 543 |  |  | 47 |  |  | 5 |  |  | 595 |  |  | 22 |  |  | 617 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 422 |  |  | 24 |  |  | 446 |
IPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $519 |  |  |  | $24 |  |  |  | $10 |  |  |  | $553 |
Operating income | 159 |  |  | 1 |  |  | 2 |  |  | 162 |
Net income available for common stock |  |  |  |  |  |  | 148 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $561 |  |  |  | $25 |  |  |  | $11 |  |  |  | $597 |
Operating income (loss) | 175 |  |  | (4 | ) |  | 3 |  |  | 174 |
Net income available for common stock |  |  |  |  |  |  | 141 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $1,332 |  |  |  | $141 |  |  |  | $31 |  |  |  | $1,504 |
Operating income | 308 |  |  | 34 |  |  | 5 |  |  | 347 |
Net income available for common stock |  |  |  |  |  |  | 290 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $1,373 |  |  |  | $188 |  |  |  | $32 |  |  |  | $1,593 |
Operating income | 291 |  |  | 26 |  |  | 5 |  |  | 322 |
Net income available for common stock |  |  |  |  |  |  | 239 |
WPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $333 |  |  |  | $18 |  |  |  | $— |  |  |  | $351 |
Operating income (loss) | 92 |  |  | (2 | ) |  | (1 | ) |  | 89 |
Net income |  |  |  |  |  |  | 73 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $355 |  |  |  | $17 |  |  |  | $— |  |  |  | $372 |
Operating income (loss) | 109 |  |  | (1 | ) |  | — |  |  | 108 |
Net income |  |  |  |  |  |  | 76 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $925 |  |  |  | $112 |  |  |  | $1 |  |  |  | $1,038 |
Operating income | 241 |  |  | 14 |  |  | — |  |  | 255 |
Net income |  |  |  |  |  |  | 220 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $977 |  |  |  | $135 |  |  |  | $1 |  |  |  | $1,113 |
Operating income | 252 |  |  | 21 |  |  | — |  |  | 273 |
Net income |  |  |  |  |  |  | 183 |
IPL [Member] |
Segment Reporting Information [Line Items] |
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, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $852 |  |  |  | $42 |  |  |  | $10 |  |  |  | $904 |  |  |  | $16 |  |  |  | $920 |
Operating income (loss) | 251 |  |  | (1 | ) |  | 1 |  |  | 251 |  |  | 21 |  |  | 272 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 221 |  |  | 25 |  |  | 246 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $916 |  |  |  | $42 |  |  |  | $11 |  |  |  | $969 |  |  |  | $21 |  |  |  | $990 |
Operating income (loss) | 284 |  |  | (5 | ) |  | 3 |  |  | 282 |  |  | 8 |  |  | 290 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 217 |  |  | 9 |  |  | 226 |
Alliant Energy |  |  |  |  |  |  |  |  | ATC Holdings, |  | Alliant
| Utility |  | Non-Utility, |  | Energy
| Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
| (in millions)
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,257 |  |  |  | $253 |  |  |  | $32 |  |  |  | $2,542 |  |  |  | $57 |  |  |  | $2,599 |
Operating income | 549 |  |  | 48 |  |  | 5 |  |  | 602 |  |  | 26 |  |  | 628 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 510 |  |  | 40 |  |  | 550 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,350 |  |  |  | $323 |  |  |  | $33 |  |  |  | $2,706 |  |  |  | $62 |  |  |  | $2,768 |
Operating income | 543 |  |  | 47 |  |  | 5 |  |  | 595 |  |  | 22 |  |  | 617 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 422 |  |  | 24 |  |  | 446 |
IPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $519 |  |  |  | $24 |  |  |  | $10 |  |  |  | $553 |
Operating income | 159 |  |  | 1 |  |  | 2 |  |  | 162 |
Net income available for common stock |  |  |  |  |  |  | 148 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $561 |  |  |  | $25 |  |  |  | $11 |  |  |  | $597 |
Operating income (loss) | 175 |  |  | (4 | ) |  | 3 |  |  | 174 |
Net income available for common stock |  |  |  |  |  |  | 141 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $1,332 |  |  |  | $141 |  |  |  | $31 |  |  |  | $1,504 |
Operating income | 308 |  |  | 34 |  |  | 5 |  |  | 347 |
Net income available for common stock |  |  |  |  |  |  | 290 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $1,373 |  |  |  | $188 |  |  |  | $32 |  |  |  | $1,593 |
Operating income | 291 |  |  | 26 |  |  | 5 |  |  | 322 |
Net income available for common stock |  |  |  |  |  |  | 239 |
WPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $333 |  |  |  | $18 |  |  |  | $— |  |  |  | $351 |
Operating income (loss) | 92 |  |  | (2 | ) |  | (1 | ) |  | 89 |
Net income |  |  |  |  |  |  | 73 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $355 |  |  |  | $17 |  |  |  | $— |  |  |  | $372 |
Operating income (loss) | 109 |  |  | (1 | ) |  | — |  |  | 108 |
Net income |  |  |  |  |  |  | 76 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $925 |  |  |  | $112 |  |  |  | $1 |  |  |  | $1,038 |
Operating income | 241 |  |  | 14 |  |  | — |  |  | 255 |
Net income |  |  |  |  |  |  | 220 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $977 |  |  |  | $135 |  |  |  | $1 |  |  |  | $1,113 |
Operating income | 252 |  |  | 21 |  |  | — |  |  | 273 |
Net income |  |  |  |  |  |  | 183 |
WPL [Member] |
Segment Reporting Information [Line Items] |
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, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $852 |  |  |  | $42 |  |  |  | $10 |  |  |  | $904 |  |  |  | $16 |  |  |  | $920 |
Operating income (loss) | 251 |  |  | (1 | ) |  | 1 |  |  | 251 |  |  | 21 |  |  | 272 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 221 |  |  | 25 |  |  | 246 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $916 |  |  |  | $42 |  |  |  | $11 |  |  |  | $969 |  |  |  | $21 |  |  |  | $990 |
Operating income (loss) | 284 |  |  | (5 | ) |  | 3 |  |  | 282 |  |  | 8 |  |  | 290 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 217 |  |  | 9 |  |  | 226 |
Alliant Energy |  |  |  |  |  |  |  |  | ATC Holdings, |  | Alliant
| Utility |  | Non-Utility, |  | Energy
| Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
| (in millions)
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,257 |  |  |  | $253 |  |  |  | $32 |  |  |  | $2,542 |  |  |  | $57 |  |  |  | $2,599 |
Operating income | 549 |  |  | 48 |  |  | 5 |  |  | 602 |  |  | 26 |  |  | 628 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 510 |  |  | 40 |  |  | 550 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,350 |  |  |  | $323 |  |  |  | $33 |  |  |  | $2,706 |  |  |  | $62 |  |  |  | $2,768 |
Operating income | 543 |  |  | 47 |  |  | 5 |  |  | 595 |  |  | 22 |  |  | 617 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 422 |  |  | 24 |  |  | 446 |
IPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $519 |  |  |  | $24 |  |  |  | $10 |  |  |  | $553 |
Operating income | 159 |  |  | 1 |  |  | 2 |  |  | 162 |
Net income available for common stock |  |  |  |  |  |  | 148 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $561 |  |  |  | $25 |  |  |  | $11 |  |  |  | $597 |
Operating income (loss) | 175 |  |  | (4 | ) |  | 3 |  |  | 174 |
Net income available for common stock |  |  |  |  |  |  | 141 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $1,332 |  |  |  | $141 |  |  |  | $31 |  |  |  | $1,504 |
Operating income | 308 |  |  | 34 |  |  | 5 |  |  | 347 |
Net income available for common stock |  |  |  |  |  |  | 290 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $1,373 |  |  |  | $188 |  |  |  | $32 |  |  |  | $1,593 |
Operating income | 291 |  |  | 26 |  |  | 5 |  |  | 322 |
Net income available for common stock |  |  |  |  |  |  | 239 |
WPL | Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $333 |  |  |  | $18 |  |  |  | $— |  |  |  | $351 |
Operating income (loss) | 92 |  |  | (2 | ) |  | (1 | ) |  | 89 |
Net income |  |  |  |  |  |  | 73 |
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $355 |  |  |  | $17 |  |  |  | $— |  |  |  | $372 |
Operating income (loss) | 109 |  |  | (1 | ) |  | — |  |  | 108 |
Net income |  |  |  |  |  |  | 76 |
Nine Months Ended September 30, 2020 |  |  |  |  |  |  |
Revenues |  | $925 |  |  |  | $112 |  |  |  | $1 |  |  |  | $1,038 |
Operating income | 241 |  |  | 14 |  |  | — |  |  | 255 |
Net income |  |  |  |  |  |  | 220 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $977 |  |  |  | $135 |  |  |  | $1 |  |  |  | $1,113 |
Operating income | 252 |  |  | 21 |  |  | — |  |  | 273 |
Net income |  |  |  |  |  |  | 183 |

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- Definition The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -URI http://asc.fasb.org/topic&trid=2134510 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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