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v3.19.3.a.u2

Disaggregation of Revenues (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disaggregation of Revenue [Line Items] |  |  |
Revenues | $ 3,647.7 | $ 3,534.5 | $ 3,382.2
IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 2,089.6 | 2,042.3 | 1,870.3
WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 1,475.7 | 1,452.6 | 1,472.8
Electric [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 3,063.6 | 3,000.3 | 2,894.7
Electric [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 1,781.2 | 1,731.1 | 1,598.9
Electric [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 1,282.4 | 1,269.2 | 1,295.8
Electric [Member] | Retail - Residential [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 1,092.4 | 1,063.4 | 1,006.2
Electric [Member] | Retail - Residential [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 601.5 | 590.6 | 535.6
Electric [Member] | Retail - Residential [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 490.9 | 472.8 | 470.6
Electric [Member] | Retail - Commercial [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 769.7 | 735.6 | 710.3
Electric [Member] | Retail - Commercial [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 510.3 | 486.8 | 452.7
Electric [Member] | Retail - Commercial [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 259.4 | 248.8 | 257.6
Electric [Member] | Retail - Industrial [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 889.1 | 888.8 | 853.1
Electric [Member] | Retail - Industrial [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 503.9 | 500.8 | 459.7
Electric [Member] | Retail - Industrial [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 385.2 | 388.0 | 393.4
Electric [Member] | Wholesale [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 176.4 | 188.4 | 238.4
Electric [Member] | Wholesale [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 63.5 | 71.2 | 95.5
Electric [Member] | Wholesale [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 112.9 | 117.2 | 142.9
Electric [Member] | Other [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 136.0 | 124.1 | 86.7
Electric [Member] | Other [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 102.0 | 81.7 | 55.4
Electric [Member] | Other [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 34.0 | 42.4 | 31.3
Gas [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 455.2 | 446.6 | 400.9
Gas [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 264.2 | 266.2 | 226.0
Gas [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 191.0 | 180.4 | 174.9
Gas [Member] | Retail - Residential [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 259.4 | 254.4 | 224.7
Gas [Member] | Retail - Residential [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 149.3 | 152.3 | 123.2
Gas [Member] | Retail - Residential [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 110.1 | 102.1 | 101.5
Gas [Member] | Retail - Commercial [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 133.0 | 133.0 | 123.2
Gas [Member] | Retail - Commercial [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 74.9 | 75.9 | 67.9
Gas [Member] | Retail - Commercial [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 58.1 | 57.1 | 55.3
Gas [Member] | Retail - Industrial [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 16.0 | 14.9 | 16.7
Gas [Member] | Retail - Industrial [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 11.7 | 10.2 | 11.1
Gas [Member] | Retail - Industrial [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 4.3 | 4.7 | 5.6
Gas [Member] | Other [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 46.8 | 44.3 | 36.3
Gas [Member] | Other [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 28.3 | 27.8 | 23.8
Gas [Member] | Other [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 18.5 | 16.5 | 12.5
Other Utility [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 46.5 | 48.0 | 47.5
Other Utility [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 44.2 | 45.0 | 45.4
Other Utility [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 2.3 | 3.0 | 2.1
Other Utility [Member] | Other [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 9.3 | 12.8 | 12.9
Other Utility [Member] | Other [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 7.0 | 9.8 | 10.8
Other Utility [Member] | Other [Member] | WPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 2.3 | 3.0 | 2.1
Other Utility [Member] | Steam [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 37.2 | 35.2 | 34.6
Other Utility [Member] | Steam [Member] | IPL [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 37.2 | 35.2 | 34.6
Non-Utility and Other [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | 82.4 | 39.6 | 39.1
Non-Utility and Other [Member] | Other [Member] |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues | $ 82.4 | $ 39.6 | $ 39.1

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