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v3.19.1

Revenues (Tables) | 3 Months Ended
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Mar. 31, 2019
Disaggregation of Revenue [Line Items] |
Disaggregation of Revenue | 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 March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $274.7 |  |  |  | $259.4 |  |  |  | $147.5 |  |  |  | $142.2 |  |  |  | $127.2 |  |  |  | $117.2 |
Retail - commercial | 181.1 |  |  | 174.0 |  |  | 116.6 |  |  | 111.6 |  |  | 64.5 |  |  | 62.4 |
Retail - industrial | 208.7 |  |  | 201.9 |  |  | 116.1 |  |  | 114.8 |  |  | 92.6 |  |  | 87.1 |
Wholesale | 46.5 |  |  | 53.8 |  |  | 16.9 |  |  | 24.3 |  |  | 29.6 |  |  | 29.5 |
Bulk power and other | 32.4 |  |  | 19.6 |  |  | 22.7 |  |  | 12.8 |  |  | 9.7 |  |  | 6.8 |
Total Electric Utility | 743.4 |  |  | 708.7 |  |  | 419.8 |  |  | 405.7 |  |  | 323.6 |  |  | 303.0 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 131.8 |  |  | 110.6 |  |  | 77.9 |  |  | 65.5 |  |  | 53.9 |  |  | 45.1 |
Retail - commercial | 63.6 |  |  | 57.0 |  |  | 34.8 |  |  | 31.6 |  |  | 28.8 |  |  | 25.4 |
Retail - industrial | 5.4 |  |  | 5.8 |  |  | 3.2 |  |  | 2.7 |  |  | 2.2 |  |  | 3.1 |
Transportation/other | 15.0 |  |  | 12.2 |  |  | 8.7 |  |  | 8.3 |  |  | 6.3 |  |  | 3.9 |
Total Gas Utility | 215.8 |  |  | 185.6 |  |  | 124.6 |  |  | 108.1 |  |  | 91.2 |  |  | 77.5 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8.4 |  |  | 9.4 |  |  | 8.4 |  |  | 9.4 |  |  | — |  |  | — |
Other utility | 2.7 |  |  | 3.8 |  |  | 2.3 |  |  | 2.6 |  |  | 0.4 |  |  | 1.2 |
Total Other Utility | 11.1 |  |  | 13.2 |  |  | 10.7 |  |  | 12.0 |  |  | 0.4 |  |  | 1.2 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $987.2 |  |  |  | $916.3 |  |  |  | $555.1 |  |  |  | $525.8 |  |  |  | $415.2 |  |  |  | $381.7 |
IPL [Member] |
Disaggregation of Revenue [Line Items] |
Disaggregation of Revenue | 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 March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $274.7 |  |  |  | $259.4 |  |  |  | $147.5 |  |  |  | $142.2 |  |  |  | $127.2 |  |  |  | $117.2 |
Retail - commercial | 181.1 |  |  | 174.0 |  |  | 116.6 |  |  | 111.6 |  |  | 64.5 |  |  | 62.4 |
Retail - industrial | 208.7 |  |  | 201.9 |  |  | 116.1 |  |  | 114.8 |  |  | 92.6 |  |  | 87.1 |
Wholesale | 46.5 |  |  | 53.8 |  |  | 16.9 |  |  | 24.3 |  |  | 29.6 |  |  | 29.5 |
Bulk power and other | 32.4 |  |  | 19.6 |  |  | 22.7 |  |  | 12.8 |  |  | 9.7 |  |  | 6.8 |
Total Electric Utility | 743.4 |  |  | 708.7 |  |  | 419.8 |  |  | 405.7 |  |  | 323.6 |  |  | 303.0 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 131.8 |  |  | 110.6 |  |  | 77.9 |  |  | 65.5 |  |  | 53.9 |  |  | 45.1 |
Retail - commercial | 63.6 |  |  | 57.0 |  |  | 34.8 |  |  | 31.6 |  |  | 28.8 |  |  | 25.4 |
Retail - industrial | 5.4 |  |  | 5.8 |  |  | 3.2 |  |  | 2.7 |  |  | 2.2 |  |  | 3.1 |
Transportation/other | 15.0 |  |  | 12.2 |  |  | 8.7 |  |  | 8.3 |  |  | 6.3 |  |  | 3.9 |
Total Gas Utility | 215.8 |  |  | 185.6 |  |  | 124.6 |  |  | 108.1 |  |  | 91.2 |  |  | 77.5 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8.4 |  |  | 9.4 |  |  | 8.4 |  |  | 9.4 |  |  | — |  |  | — |
Other utility | 2.7 |  |  | 3.8 |  |  | 2.3 |  |  | 2.6 |  |  | 0.4 |  |  | 1.2 |
Total Other Utility | 11.1 |  |  | 13.2 |  |  | 10.7 |  |  | 12.0 |  |  | 0.4 |  |  | 1.2 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $987.2 |  |  |  | $916.3 |  |  |  | $555.1 |  |  |  | $525.8 |  |  |  | $415.2 |  |  |  | $381.7 |
WPL [Member] |
Disaggregation of Revenue [Line Items] |
Disaggregation of Revenue | 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 March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $274.7 |  |  |  | $259.4 |  |  |  | $147.5 |  |  |  | $142.2 |  |  |  | $127.2 |  |  |  | $117.2 |
Retail - commercial | 181.1 |  |  | 174.0 |  |  | 116.6 |  |  | 111.6 |  |  | 64.5 |  |  | 62.4 |
Retail - industrial | 208.7 |  |  | 201.9 |  |  | 116.1 |  |  | 114.8 |  |  | 92.6 |  |  | 87.1 |
Wholesale | 46.5 |  |  | 53.8 |  |  | 16.9 |  |  | 24.3 |  |  | 29.6 |  |  | 29.5 |
Bulk power and other | 32.4 |  |  | 19.6 |  |  | 22.7 |  |  | 12.8 |  |  | 9.7 |  |  | 6.8 |
Total Electric Utility | 743.4 |  |  | 708.7 |  |  | 419.8 |  |  | 405.7 |  |  | 323.6 |  |  | 303.0 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 131.8 |  |  | 110.6 |  |  | 77.9 |  |  | 65.5 |  |  | 53.9 |  |  | 45.1 |
Retail - commercial | 63.6 |  |  | 57.0 |  |  | 34.8 |  |  | 31.6 |  |  | 28.8 |  |  | 25.4 |
Retail - industrial | 5.4 |  |  | 5.8 |  |  | 3.2 |  |  | 2.7 |  |  | 2.2 |  |  | 3.1 |
Transportation/other | 15.0 |  |  | 12.2 |  |  | 8.7 |  |  | 8.3 |  |  | 6.3 |  |  | 3.9 |
Total Gas Utility | 215.8 |  |  | 185.6 |  |  | 124.6 |  |  | 108.1 |  |  | 91.2 |  |  | 77.5 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 8.4 |  |  | 9.4 |  |  | 8.4 |  |  | 9.4 |  |  | — |  |  | — |
Other utility | 2.7 |  |  | 3.8 |  |  | 2.3 |  |  | 2.6 |  |  | 0.4 |  |  | 1.2 |
Total Other Utility | 11.1 |  |  | 13.2 |  |  | 10.7 |  |  | 12.0 |  |  | 0.4 |  |  | 1.2 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 16.9 |  |  | 8.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $987.2 |  |  |  | $916.3 |  |  |  | $555.1 |  |  |  | $525.8 |  |  |  | $415.2 |  |  |  | $381.7 |

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