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Revenues | 9 Months Ended
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Sep. 30, 2020
Disaggregation of Revenue [Line Items] |
Revenues from Contracts with Customers | 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
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $328 |  |  |  | $332 |  |  |  | $189 |  |  |  | $196 |  |  |  | $139 |  |  |  | $136 |
Retail - commercial | 210 |  |  | 231 |  |  | 142 |  |  | 158 |  |  | 68 |  |  | 73 |
Retail - industrial | 241 |  |  | 264 |  |  | 149 |  |  | 158 |  |  | 92 |  |  | 106 |
Wholesale | 47 |  |  | 50 |  |  | 17 |  |  | 18 |  |  | 30 |  |  | 32 |
Bulk power and other | 26 |  |  | 39 |  |  | 22 |  |  | 31 |  |  | 4 |  |  | 8 |
Total Electric Utility | 852 |  |  | 916 |  |  | 519 |  |  | 561 |  |  | 333 |  |  | 355 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 22 |  |  | 20 |  |  | 12 |  |  | 12 |  |  | 10 |  |  | 8 |
Retail - commercial | 10 |  |  | 10 |  |  | 6 |  |  | 6 |  |  | 4 |  |  | 4 |
Retail - industrial | 2 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | 1 |  |  | 1 |
Transportation/other | 8 |  |  | 9 |  |  | 5 |  |  | 5 |  |  | 3 |  |  | 4 |
Total Gas Utility | 42 |  |  | 42 |  |  | 24 |  |  | 25 |  |  | 18 |  |  | 17 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8 |  |  | 9 |  |  | 8 |  |  | 9 |  |  | — |  |  | — |
Other utility | 2 |  |  | 2 |  |  | 2 |  |  | 2 |  |  | — |  |  | — |
Total Other Utility | 10 |  |  | 11 |  |  | 10 |  |  | 11 |  |  | — |  |  | — |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $920 |  |  |  | $990 |  |  |  | $553 |  |  |  | $597 |  |  |  | $351 |  |  |  | $372 |
| Alliant Energy |  | IPL |  | WPL
Nine Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $845 |  |  |  | $840 |  |  |  | $472 |  |  |  | $470 |  |  |  | $373 |  |  |  | $370 |
Retail - commercial | 556 |  |  | 583 |  |  | 371 |  |  | 386 |  |  | 185 |  |  | 197 |
Retail - industrial | 648 |  |  | 686 |  |  | 384 |  |  | 392 |  |  | 264 |  |  | 294 |
Wholesale | 127 |  |  | 137 |  |  | 44 |  |  | 49 |  |  | 83 |  |  | 88 |
Bulk power and other | 81 |  |  | 104 |  |  | 61 |  |  | 76 |  |  | 20 |  |  | 28 |
Total Electric Utility | 2,257 |  |  | 2,350 |  |  | 1,332 |  |  | 1,373 |  |  | 925 |  |  | 977 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 146 |  |  | 187 |  |  | 79 |  |  | 109 |  |  | 67 |  |  | 78 |
Retail - commercial | 70 |  |  | 90 |  |  | 38 |  |  | 50 |  |  | 32 |  |  | 40 |
Retail - industrial | 8 |  |  | 10 |  |  | 5 |  |  | 7 |  |  | 3 |  |  | 3 |
Transportation/other | 29 |  |  | 36 |  |  | 19 |  |  | 22 |  |  | 10 |  |  | 14 |
Total Gas Utility | 253 |  |  | 323 |  |  | 141 |  |  | 188 |  |  | 112 |  |  | 135 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 27 |  |  | 27 |  |  | 27 |  |  | 27 |  |  | — |  |  | — |
Other utility | 5 |  |  | 6 |  |  | 4 |  |  | 5 |  |  | 1 |  |  | 1 |
Total Other Utility | 32 |  |  | 33 |  |  | 31 |  |  | 32 |  |  | 1 |  |  | 1 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $2,599 |  |  |  | $2,768 |  |  |  | $1,504 |  |  |  | $1,593 |  |  |  | $1,038 |  |  |  | $1,113 |
IPL [Member] |
Disaggregation of Revenue [Line Items] |
Revenues from Contracts with Customers | 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
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $328 |  |  |  | $332 |  |  |  | $189 |  |  |  | $196 |  |  |  | $139 |  |  |  | $136 |
Retail - commercial | 210 |  |  | 231 |  |  | 142 |  |  | 158 |  |  | 68 |  |  | 73 |
Retail - industrial | 241 |  |  | 264 |  |  | 149 |  |  | 158 |  |  | 92 |  |  | 106 |
Wholesale | 47 |  |  | 50 |  |  | 17 |  |  | 18 |  |  | 30 |  |  | 32 |
Bulk power and other | 26 |  |  | 39 |  |  | 22 |  |  | 31 |  |  | 4 |  |  | 8 |
Total Electric Utility | 852 |  |  | 916 |  |  | 519 |  |  | 561 |  |  | 333 |  |  | 355 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 22 |  |  | 20 |  |  | 12 |  |  | 12 |  |  | 10 |  |  | 8 |
Retail - commercial | 10 |  |  | 10 |  |  | 6 |  |  | 6 |  |  | 4 |  |  | 4 |
Retail - industrial | 2 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | 1 |  |  | 1 |
Transportation/other | 8 |  |  | 9 |  |  | 5 |  |  | 5 |  |  | 3 |  |  | 4 |
Total Gas Utility | 42 |  |  | 42 |  |  | 24 |  |  | 25 |  |  | 18 |  |  | 17 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8 |  |  | 9 |  |  | 8 |  |  | 9 |  |  | — |  |  | — |
Other utility | 2 |  |  | 2 |  |  | 2 |  |  | 2 |  |  | — |  |  | — |
Total Other Utility | 10 |  |  | 11 |  |  | 10 |  |  | 11 |  |  | — |  |  | — |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $920 |  |  |  | $990 |  |  |  | $553 |  |  |  | $597 |  |  |  | $351 |  |  |  | $372 |
| Alliant Energy |  | IPL |  | WPL
Nine Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $845 |  |  |  | $840 |  |  |  | $472 |  |  |  | $470 |  |  |  | $373 |  |  |  | $370 |
Retail - commercial | 556 |  |  | 583 |  |  | 371 |  |  | 386 |  |  | 185 |  |  | 197 |
Retail - industrial | 648 |  |  | 686 |  |  | 384 |  |  | 392 |  |  | 264 |  |  | 294 |
Wholesale | 127 |  |  | 137 |  |  | 44 |  |  | 49 |  |  | 83 |  |  | 88 |
Bulk power and other | 81 |  |  | 104 |  |  | 61 |  |  | 76 |  |  | 20 |  |  | 28 |
Total Electric Utility | 2,257 |  |  | 2,350 |  |  | 1,332 |  |  | 1,373 |  |  | 925 |  |  | 977 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 146 |  |  | 187 |  |  | 79 |  |  | 109 |  |  | 67 |  |  | 78 |
Retail - commercial | 70 |  |  | 90 |  |  | 38 |  |  | 50 |  |  | 32 |  |  | 40 |
Retail - industrial | 8 |  |  | 10 |  |  | 5 |  |  | 7 |  |  | 3 |  |  | 3 |
Transportation/other | 29 |  |  | 36 |  |  | 19 |  |  | 22 |  |  | 10 |  |  | 14 |
Total Gas Utility | 253 |  |  | 323 |  |  | 141 |  |  | 188 |  |  | 112 |  |  | 135 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 27 |  |  | 27 |  |  | 27 |  |  | 27 |  |  | — |  |  | — |
Other utility | 5 |  |  | 6 |  |  | 4 |  |  | 5 |  |  | 1 |  |  | 1 |
Total Other Utility | 32 |  |  | 33 |  |  | 31 |  |  | 32 |  |  | 1 |  |  | 1 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $2,599 |  |  |  | $2,768 |  |  |  | $1,504 |  |  |  | $1,593 |  |  |  | $1,038 |  |  |  | $1,113 |
WPL [Member] |
Disaggregation of Revenue [Line Items] |
Revenues from Contracts with Customers | 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
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $328 |  |  |  | $332 |  |  |  | $189 |  |  |  | $196 |  |  |  | $139 |  |  |  | $136 |
Retail - commercial | 210 |  |  | 231 |  |  | 142 |  |  | 158 |  |  | 68 |  |  | 73 |
Retail - industrial | 241 |  |  | 264 |  |  | 149 |  |  | 158 |  |  | 92 |  |  | 106 |
Wholesale | 47 |  |  | 50 |  |  | 17 |  |  | 18 |  |  | 30 |  |  | 32 |
Bulk power and other | 26 |  |  | 39 |  |  | 22 |  |  | 31 |  |  | 4 |  |  | 8 |
Total Electric Utility | 852 |  |  | 916 |  |  | 519 |  |  | 561 |  |  | 333 |  |  | 355 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 22 |  |  | 20 |  |  | 12 |  |  | 12 |  |  | 10 |  |  | 8 |
Retail - commercial | 10 |  |  | 10 |  |  | 6 |  |  | 6 |  |  | 4 |  |  | 4 |
Retail - industrial | 2 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | 1 |  |  | 1 |
Transportation/other | 8 |  |  | 9 |  |  | 5 |  |  | 5 |  |  | 3 |  |  | 4 |
Total Gas Utility | 42 |  |  | 42 |  |  | 24 |  |  | 25 |  |  | 18 |  |  | 17 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8 |  |  | 9 |  |  | 8 |  |  | 9 |  |  | — |  |  | — |
Other utility | 2 |  |  | 2 |  |  | 2 |  |  | 2 |  |  | — |  |  | — |
Total Other Utility | 10 |  |  | 11 |  |  | 10 |  |  | 11 |  |  | — |  |  | — |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $920 |  |  |  | $990 |  |  |  | $553 |  |  |  | $597 |  |  |  | $351 |  |  |  | $372 |
| Alliant Energy |  | IPL |  | WPL
Nine Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $845 |  |  |  | $840 |  |  |  | $472 |  |  |  | $470 |  |  |  | $373 |  |  |  | $370 |
Retail - commercial | 556 |  |  | 583 |  |  | 371 |  |  | 386 |  |  | 185 |  |  | 197 |
Retail - industrial | 648 |  |  | 686 |  |  | 384 |  |  | 392 |  |  | 264 |  |  | 294 |
Wholesale | 127 |  |  | 137 |  |  | 44 |  |  | 49 |  |  | 83 |  |  | 88 |
Bulk power and other | 81 |  |  | 104 |  |  | 61 |  |  | 76 |  |  | 20 |  |  | 28 |
Total Electric Utility | 2,257 |  |  | 2,350 |  |  | 1,332 |  |  | 1,373 |  |  | 925 |  |  | 977 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 146 |  |  | 187 |  |  | 79 |  |  | 109 |  |  | 67 |  |  | 78 |
Retail - commercial | 70 |  |  | 90 |  |  | 38 |  |  | 50 |  |  | 32 |  |  | 40 |
Retail - industrial | 8 |  |  | 10 |  |  | 5 |  |  | 7 |  |  | 3 |  |  | 3 |
Transportation/other | 29 |  |  | 36 |  |  | 19 |  |  | 22 |  |  | 10 |  |  | 14 |
Total Gas Utility | 253 |  |  | 323 |  |  | 141 |  |  | 188 |  |  | 112 |  |  | 135 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 27 |  |  | 27 |  |  | 27 |  |  | 27 |  |  | — |  |  | — |
Other utility | 5 |  |  | 6 |  |  | 4 |  |  | 5 |  |  | 1 |  |  | 1 |
Total Other Utility | 32 |  |  | 33 |  |  | 31 |  |  | 32 |  |  | 1 |  |  | 1 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 57 |  |  | 62 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $2,599 |  |  |  | $2,768 |  |  |  | $1,504 |  |  |  | $1,593 |  |  |  | $1,038 |  |  |  | $1,113 |

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- Definition The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -URI http://asc.fasb.org/topic&trid=49130388 + Details
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