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Debt | 9 Months Ended
--- | ---
Sep. 30, 2020
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2020 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $422 |  | $— |  | $139
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $578 |  | $250 |  | $161
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Maximum amount outstanding (based on daily outstanding balances) |  | $422 |  |  |  | $472 |  |  |  | $— |  |  |  | $— |  |  |  | $139 |  |  |  | $90 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $400 |  |  |  | $— |  |  |  | $— |  |  |  | $83 |  |  |  | $27 |
Weighted average interest rates | 0.2% |  | 2.5% |  | N/A |  | N/A |  | 0.2% |  | 2.3%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $463 |  |  |  | $601 |  |  |  | $8 |  |  |  | $50 |  |  |  | $212 |  |  |  | $195 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $476 |  |  |  | $— |  |  |  | $— |  |  |  | $86 |  |  |  | $102 |
Weighted average interest rates | 1.1% |  | 2.6% |  | 0.5% |  | 2.8% |  | 1.2% |  | 2.5%
NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of September 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement. In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures. In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2020 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $422 |  | $— |  | $139
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $578 |  | $250 |  | $161
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Maximum amount outstanding (based on daily outstanding balances) |  | $422 |  |  |  | $472 |  |  |  | $— |  |  |  | $— |  |  |  | $139 |  |  |  | $90 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $400 |  |  |  | $— |  |  |  | $— |  |  |  | $83 |  |  |  | $27 |
Weighted average interest rates | 0.2% |  | 2.5% |  | N/A |  | N/A |  | 0.2% |  | 2.3%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $463 |  |  |  | $601 |  |  |  | $8 |  |  |  | $50 |  |  |  | $212 |  |  |  | $195 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $476 |  |  |  | $— |  |  |  | $— |  |  |  | $86 |  |  |  | $102 |
Weighted average interest rates | 1.1% |  | 2.6% |  | 0.5% |  | 2.8% |  | 1.2% |  | 2.5%
NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of September 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement. In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures. In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2020 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $422 |  | $— |  | $139
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $578 |  | $250 |  | $161
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2020 |  | 2019 |  | 2020 |  | 2019 |  | 2020 |  | 2019
Maximum amount outstanding (based on daily outstanding balances) |  | $422 |  |  |  | $472 |  |  |  | $— |  |  |  | $— |  |  |  | $139 |  |  |  | $90 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $400 |  |  |  | $— |  |  |  | $— |  |  |  | $83 |  |  |  | $27 |
Weighted average interest rates | 0.2% |  | 2.5% |  | N/A |  | N/A |  | 0.2% |  | 2.3%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $463 |  |  |  | $601 |  |  |  | $8 |  |  |  | $50 |  |  |  | $212 |  |  |  | $195 |
Average amount outstanding (based on daily outstanding balances) |  | $252 |  |  |  | $476 |  |  |  | $— |  |  |  | $— |  |  |  | $86 |  |  |  | $102 |
Weighted average interest rates | 1.1% |  | 2.6% |  | 0.5% |  | 2.8% |  | 1.2% |  | 2.5%
NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of September 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement. In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures. In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + Details
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