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Debt (Schedule Of Debt Maturities) (Details) $ in Millions | Dec. 31, 2018 USD ($)
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2019 | $ 256
2020 | 657
2021 | 8
2022 | 333
2023 | 408
IPL [Member] |
2019 | 0
2020 | 200
2021 | 0
2022 | 0
2023 | 0
WPL [Member] |
2019 | 250
2020 | 150
2021 | 0
2022 | 250
2023 | 0
Corporate Services [Member] |
2019 | 0
2020 | 0
2021 | 0
2022 | 75
2023 | 0
Alliant Energy Finance, LLC [Member] |
2019 | 6
2020 | 307
2021 | 8
2022 | 8
2023 | $ 408

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- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
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