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Debt | 3 Months Ended
--- | ---
Mar. 31, 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):
March 31, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $336.4 |  | $— |  | $30.6
Commercial paper weighted average interest rates | 2.3% |  | N/A |  | 1.8%
Available credit facility capacity (a) | $617.7 |  | $204.1 |  | $319.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $336.4 |  | $325.5 |  | $3.0 |  | $9.2 |  | $36.7 |  | $113.6
Average amount outstanding (based on daily outstanding balances) | $310.1 |  | $276.5 |  | $— |  | $0.1 |  | $11.5 |  | $79.1
Weighted average interest rates | 1.9% |  | 0.9% |  | 1.8% |  | 1.1% |  | 1.6% |  | 0.7%
(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, 2018.
NOTE 7(b) Long-term Debt - As of March 31, 2018, $45.9 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, 2018, this commercial paper balance had a 2.3% interest rate. In April 2018, AEF entered into a $300 million variable-rate (2.3% at April 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.
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):
March 31, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $336.4 |  | $— |  | $30.6
Commercial paper weighted average interest rates | 2.3% |  | N/A |  | 1.8%
Available credit facility capacity (a) | $617.7 |  | $204.1 |  | $319.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $336.4 |  | $325.5 |  | $3.0 |  | $9.2 |  | $36.7 |  | $113.6
Average amount outstanding (based on daily outstanding balances) | $310.1 |  | $276.5 |  | $— |  | $0.1 |  | $11.5 |  | $79.1
Weighted average interest rates | 1.9% |  | 0.9% |  | 1.8% |  | 1.1% |  | 1.6% |  | 0.7%
(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, 2018.
NOTE 7(b) Long-term Debt - As of March 31, 2018, $45.9 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, 2018, this commercial paper balance had a 2.3% interest rate.
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):
March 31, 2018 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $336.4 |  | $— |  | $30.6
Commercial paper weighted average interest rates | 2.3% |  | N/A |  | 1.8%
Available credit facility capacity (a) | $617.7 |  | $204.1 |  | $319.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended March 31 | 2018 |  | 2017 |  | 2018 |  | 2017 |  | 2018 |  | 2017
Maximum amount outstanding (based on daily outstanding balances) | $336.4 |  | $325.5 |  | $3.0 |  | $9.2 |  | $36.7 |  | $113.6
Average amount outstanding (based on daily outstanding balances) | $310.1 |  | $276.5 |  | $— |  | $0.1 |  | $11.5 |  | $79.1
Weighted average interest rates | 1.9% |  | 0.9% |  | 1.8% |  | 1.1% |  | 1.6% |  | 0.7%
(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, 2018.

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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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