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Summary Of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2022
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
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
Electric - generation | 3.4% |  | 3.4% |  | 3.5% |  | 3.4% |  | 3.5% |  | 3.5%
Electric - distribution | 2.8% |  | 2.9% |  | 2.8% |  | 2.5% |  | 2.6% |  | 2.6%
Electric - other | 5.7% |  | 5.7% |  | 5.2% |  | 6.8% |  | 7.4% |  | 6.1%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.4% |  | 2.4% |  | 2.4%
Other | 6.1% |  | 6.1% |  | 6.3% |  | 4.9% |  | 5.4% |  | 5.9%
In December 2021, the PSCW issued an order approving the implementation of updated depreciation rates for WPL effective January 1, 2023 as a result of a recently completed depreciation study. WPL estimates the new average rates of depreciation for its electric generation, electric distribution and gas properties will be approximately 3.6%, 2.7% and 2.9%, respectively, during 2023.
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2022 |  | 2021 |  | 2020
IPL (Wind generation CWIP) | 6.9% |  | 7.0% |  | 7.1%
IPL (other CWIP) | 7.0% |  | 7.2% |  | 7.2%
WPL (retail jurisdiction) | 7.0% |  | 7.0% |  | 7.0%
WPL (wholesale jurisdiction) | 6.2% |  | 5.6% |  | 6.3%
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
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
Electric - generation | 3.4% |  | 3.4% |  | 3.5% |  | 3.4% |  | 3.5% |  | 3.5%
Electric - distribution | 2.8% |  | 2.9% |  | 2.8% |  | 2.5% |  | 2.6% |  | 2.6%
Electric - other | 5.7% |  | 5.7% |  | 5.2% |  | 6.8% |  | 7.4% |  | 6.1%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.4% |  | 2.4% |  | 2.4%
Other | 6.1% |  | 6.1% |  | 6.3% |  | 4.9% |  | 5.4% |  | 5.9%
In December 2021, the PSCW issued an order approving the implementation of updated depreciation rates for WPL effective January 1, 2023 as a result of a recently completed depreciation study. WPL estimates the new average rates of depreciation for its electric generation, electric distribution and gas properties will be approximately 3.6%, 2.7% and 2.9%, respectively, during 2023.
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2022 |  | 2021 |  | 2020
IPL (Wind generation CWIP) | 6.9% |  | 7.0% |  | 7.1%
IPL (other CWIP) | 7.0% |  | 7.2% |  | 7.2%
WPL (retail jurisdiction) | 7.0% |  | 7.0% |  | 7.0%
WPL (wholesale jurisdiction) | 6.2% |  | 5.6% |  | 6.3%
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
| 2022 |  | 2021 |  | 2020 |  | 2022 |  | 2021 |  | 2020
Electric - generation | 3.4% |  | 3.4% |  | 3.5% |  | 3.4% |  | 3.5% |  | 3.5%
Electric - distribution | 2.8% |  | 2.9% |  | 2.8% |  | 2.5% |  | 2.6% |  | 2.6%
Electric - other | 5.7% |  | 5.7% |  | 5.2% |  | 6.8% |  | 7.4% |  | 6.1%
Gas | 3.3% |  | 3.3% |  | 3.3% |  | 2.4% |  | 2.4% |  | 2.4%
Other | 6.1% |  | 6.1% |  | 6.3% |  | 4.9% |  | 5.4% |  | 5.9%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2022 |  | 2021 |  | 2020
IPL (Wind generation CWIP) | 6.9% |  | 7.0% |  | 7.1%
IPL (other CWIP) | 7.0% |  | 7.2% |  | 7.2%
WPL (retail jurisdiction) | 7.0% |  | 7.0% |  | 7.0%
WPL (wholesale jurisdiction) | 6.2% |  | 5.6% |  | 6.3%

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=84167750&loc=d3e42232-110370 + Details
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