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Debt | 6 Months Ended
--- | ---
Jun. 30, 2016
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):
| Alliant Energy |  | Parent |  |  |  |
June 30, 2016 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $220.6 |  | $174.8 |  | $— |  | $45.8
Weighted average remaining maturity | 2 days |  | 2 days |  | N/A |  | 1 day
Weighted average interest rates | 0.6% |  | 0.6% |  | N/A |  | 0.4%
Available credit facility capacity (a) | $712.4 |  | $125.2 |  | $233.0 |  | $354.2
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2016 |  | 2015 |  | 2016 |  | 2015 |  | 2016 |  | 2015
Maximum amount outstanding (based on daily outstanding balances) |  | $229.9 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $213.0 |  |  |  | $93.2 |  |  |  | $— |  |  |  | $0.1 |  |  | $37.4 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.5 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $242.6 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $206.0 |  |  |  | $110.5 |  |  |  | $— |  |  |  | $0.1 |  |  | $31.6 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.4 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2016.
NOTE 7(b) Long-term Debt - As of June 30, 2016, $67.0 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 long-term credit facilities that back-stop 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 June 30, 2016, this commercial paper balance had a remaining maturity of 1 day and a 0.6% interest rate.
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):
| Alliant Energy |  | Parent |  |  |  |
June 30, 2016 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $220.6 |  | $174.8 |  | $— |  | $45.8
Weighted average remaining maturity | 2 days |  | 2 days |  | N/A |  | 1 day
Weighted average interest rates | 0.6% |  | 0.6% |  | N/A |  | 0.4%
Available credit facility capacity (a) | $712.4 |  | $125.2 |  | $233.0 |  | $354.2
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2016 |  | 2015 |  | 2016 |  | 2015 |  | 2016 |  | 2015
Maximum amount outstanding (based on daily outstanding balances) |  | $229.9 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $213.0 |  |  |  | $93.2 |  |  |  | $— |  |  |  | $0.1 |  |  | $37.4 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.5 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $242.6 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $206.0 |  |  |  | $110.5 |  |  |  | $— |  |  |  | $0.1 |  |  | $31.6 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.4 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2016.
NOTE 7(b) Long-term Debt - As of June 30, 2016, $67.0 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 long-term credit facilities that back-stop 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 June 30, 2016, this commercial paper balance had a remaining maturity of 1 day and a 0.6% 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):
| Alliant Energy |  | Parent |  |  |  |
June 30, 2016 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $220.6 |  | $174.8 |  | $— |  | $45.8
Weighted average remaining maturity | 2 days |  | 2 days |  | N/A |  | 1 day
Weighted average interest rates | 0.6% |  | 0.6% |  | N/A |  | 0.4%
Available credit facility capacity (a) | $712.4 |  | $125.2 |  | $233.0 |  | $354.2
| Alliant Energy |  | IPL |  | WPL
Three Months Ended June 30 | 2016 |  | 2015 |  | 2016 |  | 2015 |  | 2016 |  | 2015
Maximum amount outstanding (based on daily outstanding balances) |  | $229.9 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $213.0 |  |  |  | $93.2 |  |  |  | $— |  |  |  | $0.1 |  |  | $37.4 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.5 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
Six Months Ended June 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $242.6 |  |  |  | $152.6 |  |  |  | $1.7 |  |  |  | $9.7 |  |  | $62.9 |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $206.0 |  |  |  | $110.5 |  |  |  | $— |  |  |  | $0.1 |  |  | $31.6 |  |  | $— |
Weighted average interest rates | 0.6 | % |  | 0.4 | % |  | 0.6 | % |  | 0.5 | % |  | 0.4% |  | N/A |
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2016.

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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 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20,22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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