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Asset Retirement Obligations | 3 Months Ended
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Mar. 31, 2019
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 three months ended March 31, 2019 is as follows (in millions):
| Alliant Energy |  | IPL
Balance, January 1 |  | $177.5 |  |  |  | $118.3 |
Liabilities settled | (0.7 | ) |  | (0.6 | )
Liabilities incurred (a) | 25.9 |  |  | 25.9 |
Accretion expense | 1.6 |  |  | 1.0 |
Balance, March 31 |  | $204.3 |  |  |  | $144.6 |
(a) | During the three months ended March 31, 2019, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Upland Prairie and English Farms wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.
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 three months ended March 31, 2019 is as follows (in millions):
| Alliant Energy |  | IPL
Balance, January 1 |  | $177.5 |  |  |  | $118.3 |
Liabilities settled | (0.7 | ) |  | (0.6 | )
Liabilities incurred (a) | 25.9 |  |  | 25.9 |
Accretion expense | 1.6 |  |  | 1.0 |
Balance, March 31 |  | $204.3 |  |  |  | $144.6 |
(a) | During the three months ended March 31, 2019, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Upland Prairie and English Farms wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

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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://www.xbrl.org/2003/role/presentationRef -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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