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Debt (Tables) | 6 Months Ended
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Jun. 30, 2024
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
June 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $52 |  | $— |  | $—
Weighted average interest rates | 5.5% |  | —% |  | —%
Available credit facility capacity | $948 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $435 |  | $391 |  | $19 |  | $70 |  | $57 |  | $91
Average amount outstanding (based on daily outstanding balances) | $275 |  | $88 |  | $2 |  | $6 |  | $8 |  | $18
Weighted average interest rates | 5.5% |  | 5.3% |  | 5.5% |  | 5.3% |  | 5.4% |  | 5.2%
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $381 |  | $330 |  | $1 |  | $3 |  | $131 |  | $160
Weighted average interest rates | 5.5% |  | 4.8% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.8%
IPL [Member] |
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
June 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $52 |  | $— |  | $—
Weighted average interest rates | 5.5% |  | —% |  | —%
Available credit facility capacity | $948 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $435 |  | $391 |  | $19 |  | $70 |  | $57 |  | $91
Average amount outstanding (based on daily outstanding balances) | $275 |  | $88 |  | $2 |  | $6 |  | $8 |  | $18
Weighted average interest rates | 5.5% |  | 5.3% |  | 5.5% |  | 5.3% |  | 5.4% |  | 5.2%
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $381 |  | $330 |  | $1 |  | $3 |  | $131 |  | $160
Weighted average interest rates | 5.5% |  | 4.8% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.8%
WPL [Member] |
Short-term Debt [Line Items] |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
June 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $52 |  | $— |  | $—
Weighted average interest rates | 5.5% |  | —% |  | —%
Available credit facility capacity | $948 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $435 |  | $391 |  | $19 |  | $70 |  | $57 |  | $91
Average amount outstanding (based on daily outstanding balances) | $275 |  | $88 |  | $2 |  | $6 |  | $8 |  | $18
Weighted average interest rates | 5.5% |  | 5.3% |  | 5.5% |  | 5.3% |  | 5.4% |  | 5.2%
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $381 |  | $330 |  | $1 |  | $3 |  | $131 |  | $160
Weighted average interest rates | 5.5% |  | 4.8% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.8%

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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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