Commitments And Contingencies (Other Purchase Commitments) (Details) $ in Millions	Dec. 31, 2023 USD ($)
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	$ 456
Minimum future commitments, 2024	253
Minimum future commitments, 2025	145
Minimum future commitments, 2026	95
Minimum future commitments, 2027	57
Minimum future commitments, Thereafter	164
Minimum future commitments, Total	1,170
Individual commitments incurred	1
Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	301
Minimum future commitments, 2024	187
Minimum future commitments, 2025	123
Minimum future commitments, 2026	78
Minimum future commitments, 2027	49
Minimum future commitments, Thereafter	142
Minimum future commitments, Total	880
Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	94
Minimum future commitments, 2024	49
Minimum future commitments, 2025	8
Minimum future commitments, 2026	8
Minimum future commitments, 2027	6
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	165
Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	61
Minimum future commitments, 2024	17
Minimum future commitments, 2025	14
Minimum future commitments, 2026	9
Minimum future commitments, 2027	2
Minimum future commitments, Thereafter	22
Minimum future commitments, Total	125
IPL [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	237
Minimum future commitments, 2024	123
Minimum future commitments, 2025	57
Minimum future commitments, 2026	45
Minimum future commitments, 2027	22
Minimum future commitments, Thereafter	47
Minimum future commitments, Total	531
IPL [Member] \| Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	165
Minimum future commitments, 2024	86
Minimum future commitments, 2025	47
Minimum future commitments, 2026	35
Minimum future commitments, 2027	14
Minimum future commitments, Thereafter	25
Minimum future commitments, Total	372
IPL [Member] \| Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	49
Minimum future commitments, 2024	35
Minimum future commitments, 2025	8
Minimum future commitments, 2026	8
Minimum future commitments, 2027	6
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	106
IPL [Member] \| Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	23
Minimum future commitments, 2024	2
Minimum future commitments, 2025	2
Minimum future commitments, 2026	2
Minimum future commitments, 2027	2
Minimum future commitments, Thereafter	22
Minimum future commitments, Total	53
WPL [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	204
Minimum future commitments, 2024	116
Minimum future commitments, 2025	77
Minimum future commitments, 2026	43
Minimum future commitments, 2027	35
Minimum future commitments, Thereafter	117
Minimum future commitments, Total	592
WPL [Member] \| Natural Gas [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	136
Minimum future commitments, 2024	101
Minimum future commitments, 2025	76
Minimum future commitments, 2026	43
Minimum future commitments, 2027	35
Minimum future commitments, Thereafter	117
Minimum future commitments, Total	508
WPL [Member] \| Coal [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	45
Minimum future commitments, 2024	14
Minimum future commitments, 2025	0
Minimum future commitments, 2026	0
Minimum future commitments, 2027	0
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	59
WPL [Member] \| Other [Member]
Long-term Purchase Commitment [Line Items]
Minimum future commitments, 2023	23
Minimum future commitments, 2024	1
Minimum future commitments, 2025	1
Minimum future commitments, 2026	0
Minimum future commitments, 2027	0
Minimum future commitments, Thereafter	0
Minimum future commitments, Total	$ 25

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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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