Commitments And Contingencies (Other Purchase Commitments) (Details) $ in Millions	Dec. 31, 2021 USD ($)
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	$ 452
Minimum future commitments, 2023	256
Minimum future commitments, 2024	177
Minimum future commitments, 2025	110
Minimum future commitments, 2026	90
Minimum future commitments, Thereafter	200
Minimum future commitments, Total	1,285
Individual commitments incurred	1
Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	307
Minimum future commitments, 2023	196
Minimum future commitments, 2024	144
Minimum future commitments, 2025	102
Minimum future commitments, 2026	88
Minimum future commitments, Thereafter	175
Minimum future commitments, Total	1,012
Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	63
Minimum future commitments, 2023	46
Minimum future commitments, 2024	25
Minimum future commitments, 2025	3
Minimum future commitments, 2026	0
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	137
Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	82
Minimum future commitments, 2023	14
Minimum future commitments, 2024	8
Minimum future commitments, 2025	5
Minimum future commitments, 2026	2
Minimum future commitments, Thereafter	25
Minimum future commitments, Total	136
IPL [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	214
Minimum future commitments, 2023	139
Minimum future commitments, 2024	103
Minimum future commitments, 2025	57
Minimum future commitments, 2026	44
Minimum future commitments, Thereafter	88
Minimum future commitments, Total	645
IPL [Member] \| Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	148
Minimum future commitments, 2023	108
Minimum future commitments, 2024	84
Minimum future commitments, 2025	52
Minimum future commitments, 2026	42
Minimum future commitments, Thereafter	65
Minimum future commitments, Total	499
IPL [Member] \| Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	32
Minimum future commitments, 2023	27
Minimum future commitments, 2024	17
Minimum future commitments, 2025	3
Minimum future commitments, 2026	0
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	79
IPL [Member] \| Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	34
Minimum future commitments, 2023	4
Minimum future commitments, 2024	2
Minimum future commitments, 2025	2
Minimum future commitments, 2026	2
Minimum future commitments, Thereafter	23
Minimum future commitments, Total	67
WPL [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	223
Minimum future commitments, 2023	108
Minimum future commitments, 2024	69
Minimum future commitments, 2025	51
Minimum future commitments, 2026	47
Minimum future commitments, Thereafter	110
Minimum future commitments, Total	608
WPL [Member] \| Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	159
Minimum future commitments, 2023	88
Minimum future commitments, 2024	60
Minimum future commitments, 2025	50
Minimum future commitments, 2026	46
Minimum future commitments, Thereafter	110
Minimum future commitments, Total	513
WPL [Member] \| Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	31
Minimum future commitments, 2023	19
Minimum future commitments, 2024	8
Minimum future commitments, 2025	0
Minimum future commitments, 2026	0
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	58
WPL [Member] \| Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2022	33
Minimum future commitments, 2023	1
Minimum future commitments, 2024	1
Minimum future commitments, 2025	1
Minimum future commitments, 2026	1
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	$ 37

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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