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Summary Of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2024
Schedule of Average Rates of Depreciation | The average rates of depreciation for electric, gas and other properties, consistent with current rate-making practices, were as follows:
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Electric - generation | 3.3% |  | 3.3% |  | 3.4% |  | 3.4% |  | 3.0% |  | 3.4%
Electric - distribution | 2.8% |  | 2.8% |  | 2.8% |  | 2.7% |  | 2.7% |  | 2.5%
Electric - other | 5.2% |  | 5.6% |  | 5.7% |  | 6.1% |  | 6.3% |  | 6.8%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.5% |  | 2.5% |  | 2.4%
Other | 4.6% |  | 6.2% |  | 6.1% |  | 4.4% |  | 4.6% |  | 4.9%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2024 |  | 2023 |  | 2022
IPL | 7.0% |  | 7.0% |  | 7.0%
WPL (retail jurisdiction) | 7.4% |  | 7.4% |  | 7.0%
WPL (wholesale jurisdiction) | 7.1% |  | 7.1% |  | 6.2%
IPL [Member] |
Schedule of Average Rates of Depreciation | The average rates of depreciation for electric, gas and other properties, consistent with current rate-making practices, were as follows:
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Electric - generation | 3.3% |  | 3.3% |  | 3.4% |  | 3.4% |  | 3.0% |  | 3.4%
Electric - distribution | 2.8% |  | 2.8% |  | 2.8% |  | 2.7% |  | 2.7% |  | 2.5%
Electric - other | 5.2% |  | 5.6% |  | 5.7% |  | 6.1% |  | 6.3% |  | 6.8%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.5% |  | 2.5% |  | 2.4%
Other | 4.6% |  | 6.2% |  | 6.1% |  | 4.4% |  | 4.6% |  | 4.9%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2024 |  | 2023 |  | 2022
IPL | 7.0% |  | 7.0% |  | 7.0%
WPL (retail jurisdiction) | 7.4% |  | 7.4% |  | 7.0%
WPL (wholesale jurisdiction) | 7.1% |  | 7.1% |  | 6.2%
WPL [Member] |
Schedule of Average Rates of Depreciation | The average rates of depreciation for electric, gas and other properties, consistent with current rate-making practices, were as follows:
| IPL |  | WPL
| 2024 |  | 2023 |  | 2022 |  | 2024 |  | 2023 |  | 2022
Electric - generation | 3.3% |  | 3.3% |  | 3.4% |  | 3.4% |  | 3.0% |  | 3.4%
Electric - distribution | 2.8% |  | 2.8% |  | 2.8% |  | 2.7% |  | 2.7% |  | 2.5%
Electric - other | 5.2% |  | 5.6% |  | 5.7% |  | 6.1% |  | 6.3% |  | 6.8%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.5% |  | 2.5% |  | 2.4%
Other | 4.6% |  | 6.2% |  | 6.1% |  | 4.4% |  | 4.6% |  | 4.9%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2024 |  | 2023 |  | 2022
IPL | 7.0% |  | 7.0% |  | 7.0%
WPL (retail jurisdiction) | 7.4% |  | 7.4% |  | 7.0%
WPL (wholesale jurisdiction) | 7.1% |  | 7.1% |  | 6.2%

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- Definition Tabular disclosure of regulation for public utility entities, including, but not limited to, rate requests, decommissioning costs and the amount of allowance for earnings on equity capitalized for rate making purposes. + References No definition available. + Details
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- Definition Tabular disclosure of public utility physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation expense and method used, including composite depreciation, and accumulated depreciation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 20 -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481834/980-20-45-1 + Details
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