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Debt (Tables) | 9 Months Ended
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Sep. 30, 2023
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2023 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $451 |  | $— |  | $120
Weighted average interest rates | 5.5% |  | —% |  | 5.4%
Available credit facility capacity | $549 |  | $250 |  | $180
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Maximum amount outstanding (based on daily outstanding balances) | $474 |  | $449 |  | $7 |  | $— |  | $125 |  | $251
Average amount outstanding (based on daily outstanding balances) | $440 |  | $353 |  | $— |  | $— |  | $86 |  | $110
Weighted average interest rates | 5.5% |  | 2.4% |  | 5.5% |  | —% |  | 5.4% |  | 2.0%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $793 |  | $577 |  | $70 |  | $— |  | $349 |  | $252
Average amount outstanding (based on daily outstanding balances) | $367 |  | $377 |  | $2 |  | $— |  | $135 |  | $160
Weighted average interest rates | 5.1% |  | 1.2% |  | 5.3% |  | —% |  | 4.9% |  | 0.9%
IPL [Member] |
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2023 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $451 |  | $— |  | $120
Weighted average interest rates | 5.5% |  | —% |  | 5.4%
Available credit facility capacity | $549 |  | $250 |  | $180
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Maximum amount outstanding (based on daily outstanding balances) | $474 |  | $449 |  | $7 |  | $— |  | $125 |  | $251
Average amount outstanding (based on daily outstanding balances) | $440 |  | $353 |  | $— |  | $— |  | $86 |  | $110
Weighted average interest rates | 5.5% |  | 2.4% |  | 5.5% |  | —% |  | 5.4% |  | 2.0%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $793 |  | $577 |  | $70 |  | $— |  | $349 |  | $252
Average amount outstanding (based on daily outstanding balances) | $367 |  | $377 |  | $2 |  | $— |  | $135 |  | $160
Weighted average interest rates | 5.1% |  | 1.2% |  | 5.3% |  | —% |  | 4.9% |  | 0.9%
WPL [Member] |
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2023 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $451 |  | $— |  | $120
Weighted average interest rates | 5.5% |  | —% |  | 5.4%
Available credit facility capacity | $549 |  | $250 |  | $180
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2023 |  | 2022 |  | 2023 |  | 2022 |  | 2023 |  | 2022
Maximum amount outstanding (based on daily outstanding balances) | $474 |  | $449 |  | $7 |  | $— |  | $125 |  | $251
Average amount outstanding (based on daily outstanding balances) | $440 |  | $353 |  | $— |  | $— |  | $86 |  | $110
Weighted average interest rates | 5.5% |  | 2.4% |  | 5.5% |  | —% |  | 5.4% |  | 2.0%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $793 |  | $577 |  | $70 |  | $— |  | $349 |  | $252
Average amount outstanding (based on daily outstanding balances) | $367 |  | $377 |  | $2 |  | $— |  | $135 |  | $160
Weighted average interest rates | 5.1% |  | 1.2% |  | 5.3% |  | —% |  | 4.9% |  | 0.9%

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- Definition Tabular disclosure of short-term debt arrangements (having initial terms of repayment within one year or the normal operating cycle, if longer) including: (1) description of the short-term debt arrangement; (2) identification of the lender or type of lender; (3) repayment terms; (4) weighted average interest rate; (5) carrying amount of funds borrowed under the specified short-term debt arrangement as of the balance sheet date; (6) description of the refinancing of a short-term obligation when that obligation is excluded from current liabilities in the balance sheet; and (7) amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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