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v3.20.2

Debt (Credit Facilities) (Details) $ in Millions | Jun. 30, 2020 USD ($)
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Debt [Line Items] |
Amount outstanding | $ 185.4
Weighted average interest rates | 0.30%
Available credit facility capacity | $ 814.6
IPL [Member] |
Debt [Line Items] |
Amount outstanding | 0.0
Available credit facility capacity | 250.0
WPL [Member] |
Debt [Line Items] |
Amount outstanding | $ 37.9
Weighted average interest rates | 0.20%
Available credit facility capacity | $ 262.1

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