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Commitments And Contingencies (Other Purchase Commitments) (Details) $ in Millions | Dec. 31, 2020 USD ($)
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Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | $ 383
Minimum future commitments, 2022 | 218
Minimum future commitments, 2023 | 165
Minimum future commitments, 2024 | 113
Minimum future commitments, 2025 | 71
Minimum future commitments, Thereafter | 214
Minimum future commitments, Total | 1,164
Individual commitments incurred | 1
Natural Gas [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 252
Minimum future commitments, 2022 | 174
Minimum future commitments, 2023 | 137
Minimum future commitments, 2024 | 105
Minimum future commitments, 2025 | 68
Minimum future commitments, Thereafter | 185
Minimum future commitments, Total | 921
Coal [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 70
Minimum future commitments, 2022 | 27
Minimum future commitments, 2023 | 17
Minimum future commitments, 2024 | 0
Minimum future commitments, 2025 | 0
Minimum future commitments, Thereafter | 0
Minimum future commitments, Total | 114
Other [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 61
Minimum future commitments, 2022 | 17
Minimum future commitments, 2023 | 11
Minimum future commitments, 2024 | 8
Minimum future commitments, 2025 | 3
Minimum future commitments, Thereafter | 29
Minimum future commitments, Total | 129
IPL [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 187
Minimum future commitments, 2022 | 109
Minimum future commitments, 2023 | 96
Minimum future commitments, 2024 | 70
Minimum future commitments, 2025 | 40
Minimum future commitments, Thereafter | 98
Minimum future commitments, Total | 600
IPL [Member] | Natural Gas [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 130
Minimum future commitments, 2022 | 88
Minimum future commitments, 2023 | 79
Minimum future commitments, 2024 | 68
Minimum future commitments, 2025 | 38
Minimum future commitments, Thereafter | 71
Minimum future commitments, Total | 474
IPL [Member] | Coal [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 32
Minimum future commitments, 2022 | 16
Minimum future commitments, 2023 | 13
Minimum future commitments, 2024 | 0
Minimum future commitments, 2025 | 0
Minimum future commitments, Thereafter | 0
Minimum future commitments, Total | 61
IPL [Member] | Other [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 25
Minimum future commitments, 2022 | 5
Minimum future commitments, 2023 | 4
Minimum future commitments, 2024 | 2
Minimum future commitments, 2025 | 2
Minimum future commitments, Thereafter | 27
Minimum future commitments, Total | 65
WPL [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 186
Minimum future commitments, 2022 | 99
Minimum future commitments, 2023 | 63
Minimum future commitments, 2024 | 38
Minimum future commitments, 2025 | 31
Minimum future commitments, Thereafter | 115
Minimum future commitments, Total | 532
WPL [Member] | Natural Gas [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 122
Minimum future commitments, 2022 | 86
Minimum future commitments, 2023 | 58
Minimum future commitments, 2024 | 37
Minimum future commitments, 2025 | 30
Minimum future commitments, Thereafter | 114
Minimum future commitments, Total | 447
WPL [Member] | Coal [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 38
Minimum future commitments, 2022 | 11
Minimum future commitments, 2023 | 4
Minimum future commitments, 2024 | 0
Minimum future commitments, 2025 | 0
Minimum future commitments, Thereafter | 0
Minimum future commitments, Total | 53
WPL [Member] | Other [Member] |
Long-term Purchase Commitment [Line Items] |
Minimum future commitments, 2021 | 26
Minimum future commitments, 2022 | 2
Minimum future commitments, 2023 | 1
Minimum future commitments, 2024 | 1
Minimum future commitments, 2025 | 1
Minimum future commitments, Thereafter | 1
Minimum future commitments, Total | $ 32

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