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Debt | 9 Months Ended
--- | ---
Sep. 30, 2017
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - In August 2017, Alliant Energy, IPL and WPL entered into a single new credit facility agreement, which expires in August 2022. The new credit facility agreement includes financial covenants similar to those that were included in the previous credit facility agreements. As of September 30, 2017, the short-term borrowing capacity under the new credit facility agreement totaled $1 billion ($300 million for Alliant Energy at the parent company level, $300 million for IPL and $400 million for WPL). Subject to certain conditions, Alliant Energy (at the parent company level), IPL and WPL may each reallocate and change its initial sublimit up to $500 million, $400 million and $500 million, respectively, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2017 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $390.3 |  | $4.0 |  | $224.6
Commercial paper weighted average interest rates | 1.2% |  | 1.4% |  | 1.1%
Available credit facility capacity (a) | $569.7 |  | $256.0 |  | $175.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $55.4
Average amount outstanding (based on daily outstanding balances) | $386.2 |  | $220.1 |  | $0.4 |  | $0.1 |  | $217.0 |  | $36.4
Weighted average interest rates | 1.3% |  | 0.6% |  | 1.4% |  | 0.6% |  | 1.1% |  | 0.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $62.9
Average amount outstanding (based on daily outstanding balances) | $323.9 |  | $210.7 |  | $0.5 |  | $— |  | $144.2 |  | $33.2
Weighted average interest rates | 1.1% |  | 0.6% |  | 1.2% |  | 0.6% |  | 1.0% |  | 0.4%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at September 30, 2017.
In July 2017, AEF entered into a $95 million, 364-day variable-rate (1.8% at September 30, 2017) term loan credit agreement (with Alliant Energy as guarantor) related to the acquisition of a non-regulated wind farm located in Oklahoma, which includes substantially the same financial covenants that are included in Alliant Energy’s current credit facility agreement. Refer to Note 5(a) for further discussion of the non-regulated wind farm acquisition. NOTE 7(b) Long-term Debt - As of September 30, 2017, $40.0 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 September 30, 2017, this commercial paper balance had a 1.4% interest rate. In October 2017, WPL issued $300 million of 3.05% debentures due 2027. The proceeds from the issuance were used by WPL to reduce commercial paper and for general corporate purposes.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - In August 2017, Alliant Energy, IPL and WPL entered into a single new credit facility agreement, which expires in August 2022. The new credit facility agreement includes financial covenants similar to those that were included in the previous credit facility agreements. As of September 30, 2017, the short-term borrowing capacity under the new credit facility agreement totaled $1 billion ($300 million for Alliant Energy at the parent company level, $300 million for IPL and $400 million for WPL). Subject to certain conditions, Alliant Energy (at the parent company level), IPL and WPL may each reallocate and change its initial sublimit up to $500 million, $400 million and $500 million, respectively, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2017 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $390.3 |  | $4.0 |  | $224.6
Commercial paper weighted average interest rates | 1.2% |  | 1.4% |  | 1.1%
Available credit facility capacity (a) | $569.7 |  | $256.0 |  | $175.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $55.4
Average amount outstanding (based on daily outstanding balances) | $386.2 |  | $220.1 |  | $0.4 |  | $0.1 |  | $217.0 |  | $36.4
Weighted average interest rates | 1.3% |  | 0.6% |  | 1.4% |  | 0.6% |  | 1.1% |  | 0.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $62.9
Average amount outstanding (based on daily outstanding balances) | $323.9 |  | $210.7 |  | $0.5 |  | $— |  | $144.2 |  | $33.2
Weighted average interest rates | 1.1% |  | 0.6% |  | 1.2% |  | 0.6% |  | 1.0% |  | 0.4%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at September 30, 2017.
In July 2017, AEF entered into a $95 million, 364-day variable-rate (1.8% at September 30, 2017) term loan credit agreement (with Alliant Energy as guarantor) related to the acquisition of a non-regulated wind farm located in Oklahoma, which includes substantially the same financial covenants that are included in Alliant Energy’s current credit facility agreement. Refer to Note 5(a) for further discussion of the non-regulated wind farm acquisition. NOTE 7(b) Long-term Debt - As of September 30, 2017, $40.0 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 September 30, 2017, this commercial paper balance had a 1.4% interest rate.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT Note 7(a) Short-term Debt - In August 2017, Alliant Energy, IPL and WPL entered into a single new credit facility agreement, which expires in August 2022. The new credit facility agreement includes financial covenants similar to those that were included in the previous credit facility agreements. As of September 30, 2017, the short-term borrowing capacity under the new credit facility agreement totaled $1 billion ($300 million for Alliant Energy at the parent company level, $300 million for IPL and $400 million for WPL). Subject to certain conditions, Alliant Energy (at the parent company level), IPL and WPL may each reallocate and change its initial sublimit up to $500 million, $400 million and $500 million, respectively, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2017 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $390.3 |  | $4.0 |  | $224.6
Commercial paper weighted average interest rates | 1.2% |  | 1.4% |  | 1.1%
Available credit facility capacity (a) | $569.7 |  | $256.0 |  | $175.4
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2017 |  | 2016 |  | 2017 |  | 2016 |  | 2017 |  | 2016
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $55.4
Average amount outstanding (based on daily outstanding balances) | $386.2 |  | $220.1 |  | $0.4 |  | $0.1 |  | $217.0 |  | $36.4
Weighted average interest rates | 1.3% |  | 0.6% |  | 1.4% |  | 0.6% |  | 1.1% |  | 0.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $424.4 |  | $248.0 |  | $20.0 |  | $3.1 |  | $271.2 |  | $62.9
Average amount outstanding (based on daily outstanding balances) | $323.9 |  | $210.7 |  | $0.5 |  | $— |  | $144.2 |  | $33.2
Weighted average interest rates | 1.1% |  | 0.6% |  | 1.2% |  | 0.6% |  | 1.0% |  | 0.4%
(a) | Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at September 30, 2017.
In July 2017, AEF entered into a $95 million, 364-day variable-rate (1.8% at September 30, 2017) term loan credit agreement (with Alliant Energy as guarantor) related to the acquisition of a non-regulated wind farm located in Oklahoma, which includes substantially the same financial covenants that are included in Alliant Energy’s current credit facility agreement. Refer to Note 5(a) for further discussion of the non-regulated wind farm acquisition. NOTE 7(b) Long-term Debt - As of September 30, 2017, $40.0 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 September 30, 2017, this commercial paper balance had a 1.4% interest rate. In October 2017, WPL issued $300 million of 3.05% debentures due 2027. The proceeds from the issuance were used by WPL to reduce commercial paper 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://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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