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Debt | 3 Months Ended
--- | ---
Mar. 31, 2019
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - In March 2019, Alliant Energy, IPL and WPL extended their single credit facility agreement by one year, which currently expires in August 2023. As of March 31, 2019, the short-term borrowing capacity under the agreement totaled $1 billion ($450 million for Alliant Energy at the parent company, $250 million for IPL and $300 million for WPL). Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
March 31, 2019 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $514.7 |  | $— |  | $138.4
Commercial paper weighted average interest rates | 2.6% |  | N/A |  | 2.5%
Available credit facility capacity (a) | $370.3 |  | $135.0 |  | $161.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Maximum amount outstanding (based on daily outstanding balances) | $600.6 |  | $336.4 |  | $50.4 |  | $3.0 |  | $195.1 |  | $36.7
Average amount outstanding (based on daily outstanding balances) | $498.8 |  | $310.1 |  | $0.6 |  | $— |  | $138.1 |  | $11.5
Weighted average interest rates | 2.7% |  | 1.9% |  | 2.8% |  | 1.8% |  | 2.5% |  | 1.6%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at March 31, 2019.
NOTE 6(b) Long-term Debt - As of March 31, 2019, $115.0 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s balance sheets due to the existence of a long-term credit facility that back-stops this commercial paper balance, along with Alliant Energy’s and IPL’s intent and ability to refinance these balances on a long-term basis. As of March 31, 2019, this commercial paper balance had a 2.7% interest rate. In April 2019, IPL issued $300 million of 3.6% senior debentures due 2029. The senior debentures were issued as green bonds, and all of the net proceeds were allocated for the construction and development of IPL’s wind projects.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - In March 2019, Alliant Energy, IPL and WPL extended their single credit facility agreement by one year, which currently expires in August 2023. As of March 31, 2019, the short-term borrowing capacity under the agreement totaled $1 billion ($450 million for Alliant Energy at the parent company, $250 million for IPL and $300 million for WPL). Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
March 31, 2019 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $514.7 |  | $— |  | $138.4
Commercial paper weighted average interest rates | 2.6% |  | N/A |  | 2.5%
Available credit facility capacity (a) | $370.3 |  | $135.0 |  | $161.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Maximum amount outstanding (based on daily outstanding balances) | $600.6 |  | $336.4 |  | $50.4 |  | $3.0 |  | $195.1 |  | $36.7
Average amount outstanding (based on daily outstanding balances) | $498.8 |  | $310.1 |  | $0.6 |  | $— |  | $138.1 |  | $11.5
Weighted average interest rates | 2.7% |  | 1.9% |  | 2.8% |  | 1.8% |  | 2.5% |  | 1.6%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at March 31, 2019.
NOTE 6(b) Long-term Debt - As of March 31, 2019, $115.0 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s balance sheets due to the existence of a long-term credit facility that back-stops this commercial paper balance, along with Alliant Energy’s and IPL’s intent and ability to refinance these balances on a long-term basis. As of March 31, 2019, this commercial paper balance had a 2.7% interest rate. In April 2019, IPL issued $300 million of 3.6% senior debentures due 2029. The senior debentures were issued as green bonds, and all of the net proceeds were allocated for the construction and development of IPL’s wind projects.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 6(a) Short-term Debt - In March 2019, Alliant Energy, IPL and WPL extended their single credit facility agreement by one year, which currently expires in August 2023. As of March 31, 2019, the short-term borrowing capacity under the agreement totaled $1 billion ($450 million for Alliant Energy at the parent company, $250 million for IPL and $300 million for WPL). Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
March 31, 2019 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $514.7 |  | $— |  | $138.4
Commercial paper weighted average interest rates | 2.6% |  | N/A |  | 2.5%
Available credit facility capacity (a) | $370.3 |  | $135.0 |  | $161.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Maximum amount outstanding (based on daily outstanding balances) | $600.6 |  | $336.4 |  | $50.4 |  | $3.0 |  | $195.1 |  | $36.7
Average amount outstanding (based on daily outstanding balances) | $498.8 |  | $310.1 |  | $0.6 |  | $— |  | $138.1 |  | $11.5
Weighted average interest rates | 2.7% |  | 1.9% |  | 2.8% |  | 1.8% |  | 2.5% |  | 1.6%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at March 31, 2019.

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + 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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