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v3.19.3.a.u2

Summary Of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2019
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
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Electric - generation | 3.8% |  | 3.6% |  | 3.5% |  | 3.6% |  | 3.6% |  | 3.5%
Electric - distribution | 2.9% |  | 2.8% |  | 2.4% |  | 2.6% |  | 2.6% |  | 2.6%
Electric - other | 5.3% |  | 4.7% |  | 4.5% |  | 5.8% |  | 5.7% |  | 6.9%
Gas | 3.3% |  | 3.2% |  | 3.4% |  | 2.5% |  | 2.5% |  | 2.5%
Other | 5.9% |  | 5.2% |  | 4.0% |  | 5.6% |  | 5.8% |  | 6.0%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2019 |  | 2018 |  | 2017
IPL (Marshalltown CWIP) | N/A |  | N/A |  | 7.8%
IPL (Wind generation CWIP) | 7.4% |  | 7.5% |  | 7.6%
IPL (other CWIP) | 7.5% |  | 7.5% |  | 7.6%
WPL (retail jurisdiction) | 6.8% |  | 7.7% |  | 7.6%
WPL (wholesale jurisdiction) | 6.9% |  | 7.2% |  | 6.0%
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
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Electric - generation | 3.8% |  | 3.6% |  | 3.5% |  | 3.6% |  | 3.6% |  | 3.5%
Electric - distribution | 2.9% |  | 2.8% |  | 2.4% |  | 2.6% |  | 2.6% |  | 2.6%
Electric - other | 5.3% |  | 4.7% |  | 4.5% |  | 5.8% |  | 5.7% |  | 6.9%
Gas | 3.3% |  | 3.2% |  | 3.4% |  | 2.5% |  | 2.5% |  | 2.5%
Other | 5.9% |  | 5.2% |  | 4.0% |  | 5.6% |  | 5.8% |  | 6.0%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2019 |  | 2018 |  | 2017
IPL (Marshalltown CWIP) | N/A |  | N/A |  | 7.8%
IPL (Wind generation CWIP) | 7.4% |  | 7.5% |  | 7.6%
IPL (other CWIP) | 7.5% |  | 7.5% |  | 7.6%
WPL (retail jurisdiction) | 6.8% |  | 7.7% |  | 7.6%
WPL (wholesale jurisdiction) | 6.9% |  | 7.2% |  | 6.0%
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
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Electric - generation | 3.8% |  | 3.6% |  | 3.5% |  | 3.6% |  | 3.6% |  | 3.5%
Electric - distribution | 2.9% |  | 2.8% |  | 2.4% |  | 2.6% |  | 2.6% |  | 2.6%
Electric - other | 5.3% |  | 4.7% |  | 4.5% |  | 5.8% |  | 5.7% |  | 6.9%
Gas | 3.3% |  | 3.2% |  | 3.4% |  | 2.5% |  | 2.5% |  | 2.5%
Other | 5.9% |  | 5.2% |  | 4.0% |  | 5.6% |  | 5.8% |  | 6.0%
Schedule of Allowance for Funds Used During Construction Rate | The AFUDC rates, computed in accordance with the prescribed regulatory formula, were as follows:
| 2019 |  | 2018 |  | 2017
IPL (Marshalltown CWIP) | N/A |  | N/A |  | 7.8%
IPL (Wind generation CWIP) | 7.4% |  | 7.5% |  | 7.6%
IPL (other CWIP) | 7.5% |  | 7.5% |  | 7.6%
WPL (retail jurisdiction) | 6.8% |  | 7.7% |  | 7.6%
WPL (wholesale jurisdiction) | 6.9% |  | 7.2% |  | 6.0%

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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, deprecation expense and method used, including composite depreciation, and accumulated deprecation. + 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 http://asc.fasb.org/extlink&oid=84167750&loc=d3e42232-110370 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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