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Debt | 9 Months Ended
--- | ---
Sep. 30, 2018
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $136.8 |  | $— |  | $38.4
Commercial paper weighted average interest rates | 2.4% |  | N/A |  | 2.2%
Available credit facility capacity | $863.2 |  | $250.0 |  | $311.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $153.3 |  | $424.4 |  | $— |  | $20.0 |  | $75.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $80.8 |  | $386.2 |  | $— |  | $0.4 |  | $23.1 |  | $217.0
Weighted average interest rates | 2.2% |  | 1.3% |  | N/A |  | 1.4% |  | 2.0% |  | 1.1%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $446.5 |  | $424.4 |  | $31.4 |  | $20.0 |  | $109.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $207.6 |  | $323.9 |  | $1.7 |  | $0.5 |  | $26.6 |  | $144.2
Weighted average interest rates | 2.1% |  | 1.1% |  | 2.3% |  | 1.2% |  | 1.9% |  | 1.0%
As discussed in Note 7(b), in June 2018, AEF retired its $95 million term loan credit agreement expiring in 2018. NOTE 7(b) Long-term Debt - In April 2018, AEF entered into a $300 million variable-rate (2.8% at September 30, 2018) term loan credit agreement (with Alliant Energy as guarantor) and used the proceeds from borrowings under this agreement for general corporate purposes. AEF’s term loan credit agreement expires in April 2020 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement. In June 2018, AEF (with Alliant Energy as guarantor) issued $400 million of 3.75% senior notes due 2023 and $300 million of 4.25% senior notes due 2028. The proceeds from the issuances were used by AEF to retire its $500 million and $95 million variable-rate term loan credit agreements expiring in 2018, to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In September 2018, IPL issued $500 million of 4.1% senior debentures due 2028. The senior debentures were issued as green bonds, and all of the net proceeds were allocated for the construction and development of wind and solar projects. In September 2018 and October 2018, IPL retired its $100 million (5.875%) and $250 million (7.25%) senior debentures, respectively.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $136.8 |  | $— |  | $38.4
Commercial paper weighted average interest rates | 2.4% |  | N/A |  | 2.2%
Available credit facility capacity | $863.2 |  | $250.0 |  | $311.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $153.3 |  | $424.4 |  | $— |  | $20.0 |  | $75.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $80.8 |  | $386.2 |  | $— |  | $0.4 |  | $23.1 |  | $217.0
Weighted average interest rates | 2.2% |  | 1.3% |  | N/A |  | 1.4% |  | 2.0% |  | 1.1%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $446.5 |  | $424.4 |  | $31.4 |  | $20.0 |  | $109.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $207.6 |  | $323.9 |  | $1.7 |  | $0.5 |  | $26.6 |  | $144.2
Weighted average interest rates | 2.1% |  | 1.1% |  | 2.3% |  | 1.2% |  | 1.9% |  | 1.0%
As discussed in Note 7(b), in June 2018, AEF retired its $95 million term loan credit agreement expiring in 2018. NOTE 7(b) Long-term Debt - In April 2018, AEF entered into a $300 million variable-rate (2.8% at September 30, 2018) term loan credit agreement (with Alliant Energy as guarantor) and used the proceeds from borrowings under this agreement for general corporate purposes. AEF’s term loan credit agreement expires in April 2020 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement. In June 2018, AEF (with Alliant Energy as guarantor) issued $400 million of 3.75% senior notes due 2023 and $300 million of 4.25% senior notes due 2028. The proceeds from the issuances were used by AEF to retire its $500 million and $95 million variable-rate term loan credit agreements expiring in 2018, to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In September 2018, IPL issued $500 million of 4.1% senior debentures due 2028. The senior debentures were issued as green bonds, and all of the net proceeds were allocated for the construction and development of wind and solar projects. In September 2018 and October 2018, IPL retired its $100 million (5.875%) and $250 million (7.25%) senior debentures, respectively.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $136.8 |  | $— |  | $38.4
Commercial paper weighted average interest rates | 2.4% |  | N/A |  | 2.2%
Available credit facility capacity | $863.2 |  | $250.0 |  | $311.6
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $153.3 |  | $424.4 |  | $— |  | $20.0 |  | $75.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $80.8 |  | $386.2 |  | $— |  | $0.4 |  | $23.1 |  | $217.0
Weighted average interest rates | 2.2% |  | 1.3% |  | N/A |  | 1.4% |  | 2.0% |  | 1.1%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $446.5 |  | $424.4 |  | $31.4 |  | $20.0 |  | $109.4 |  | $271.2
Average amount outstanding (based on daily outstanding balances) | $207.6 |  | $323.9 |  | $1.7 |  | $0.5 |  | $26.6 |  | $144.2
Weighted average interest rates | 2.1% |  | 1.1% |  | 2.3% |  | 1.2% |  | 1.9% |  | 1.0%

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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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