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Commitments And Contingencies (Tables) | 3 Months Ended
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Mar. 31, 2023
Commitments and Contingencies [Line Items] |
Other Purchase Commitments | At March 31, 2023, related minimum future commitments were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Natural gas | $1,280 |  | $565 |  | $715
Coal | 175 |  | 89 |  | 86
Other (a) | 113 |  | 53 |  | 26
| $1,568 |  | $707 |  | $827
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2023.
MGP Site Estimated Future Costs And Recorded Liabilities | At March 31, 2023, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs | $10 |  | - | $37 |  | $6 |  | - | $12 |  | $4 |  | - | $25
Current and non-current environmental liabilities | $18 |  | $8 |  | $10
IPL [Member] |
Commitments and Contingencies [Line Items] |
Other Purchase Commitments | At March 31, 2023, related minimum future commitments were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Natural gas | $1,280 |  | $565 |  | $715
Coal | 175 |  | 89 |  | 86
Other (a) | 113 |  | 53 |  | 26
| $1,568 |  | $707 |  | $827
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2023.
MGP Site Estimated Future Costs And Recorded Liabilities | At March 31, 2023, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs | $10 |  | - | $37 |  | $6 |  | - | $12 |  | $4 |  | - | $25
Current and non-current environmental liabilities | $18 |  | $8 |  | $10
WPL [Member] |
Commitments and Contingencies [Line Items] |
Other Purchase Commitments | At March 31, 2023, related minimum future commitments were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Natural gas | $1,280 |  | $565 |  | $715
Coal | 175 |  | 89 |  | 86
Other (a) | 113 |  | 53 |  | 26
| $1,568 |  | $707 |  | $827
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2023.
MGP Site Estimated Future Costs And Recorded Liabilities | At March 31, 2023, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs | $10 |  | - | $37 |  | $6 |  | - | $12 |  | $4 |  | - | $25
Current and non-current environmental liabilities | $18 |  | $8 |  | $10

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- Definition Tabular disclosure of material liabilities for remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal or abandonment of a property as a result of unanticipated contamination of the assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480102/450-20-S99-1 + Details
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- Definition Tabular disclosure of key provisions of an arrangement under which the entity has agreed to purchase goods or services over a period of time greater than one year or the normal operating cycle, if longer, including the item for which expenditures will be made, minimum quantities, milestones, time period and committed amount. + References No definition available. + Details
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