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Asset Retirement Obligations | 9 Months Ended
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Sep. 30, 2021
Asset Retirement Obligations [Line Items] |
Asset Retirement Obligations | ASSET RETIREMENT OBLIGATIONS A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the nine months ended September 30, 2021 is as follows (in millions):
| Alliant Energy |  | IPL |  |
Balance, January 1 | $251 |  | $177 |  |
Revisions in estimated cash flows | 37 |  | 32 |  |
Liabilities settled | (10) |  | (8) |  |
Liabilities incurred | 1 |  | — |  |
Accretion expense | 6 |  | 4 |  |
Balance, September 30 | $285 |  | $205 |  |
IPL [Member] |
Asset Retirement Obligations [Line Items] |
Asset Retirement Obligations | ASSET RETIREMENT OBLIGATIONS A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the nine months ended September 30, 2021 is as follows (in millions):
| Alliant Energy |  | IPL |  |
Balance, January 1 | $251 |  | $177 |  |
Revisions in estimated cash flows | 37 |  | 32 |  |
Liabilities settled | (10) |  | (8) |  |
Liabilities incurred | 1 |  | — |  |
Accretion expense | 6 |  | 4 |  |
Balance, September 30 | $285 |  | $205 |  |

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- Definition Asset Retirement Obligations [Line Items] + References No definition available. + Details
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- Definition The entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -URI http://asc.fasb.org/subtopic&trid=2175671 + Details
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- Details
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