v2.4.0.6

Debt | 9 Months Ended
--- | ---
Sep. 30, 2012
Debt Instrument [Line Items] |
Debt | DEBT (a) Short-term Debt - Information regarding commercial paper issued under Alliant Energy’s, IPL’s and WPL’s credit facilities classified as short-term debt was as follows (dollars in millions):
| Alliant Energy |  | Parent |  |  |  |
September 30, 2012 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $70.4 |  | $70.4 |  | $— |  | $—
Remaining maturity | 1 day |  | 1 day |  | N/A |  | N/A
Interest rates | 0.4% |  | 0.4% |  | N/A |  | N/A
Available credit facility capacity (a) | $879.6 |  | $229.6 |  | $250.0 |  | $400.0
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $22.1 |  |  |  | $19.5 |  |  |  | $18.0 |  |  |  | $35.6 |  |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $133.0 |  |  |  | $2.6 |  |  |  | $1.3 |  |  |  | $1.7 |  |  |  | $11.9 |  |  |  | $— |
Weighted average interest rates | 0.4 | % |  | 0.4 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | N/A |
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $96.5 |  |  |  | $35.4 |  |  |  | $54.4 |  |  |  | $35.6 |  |  |  | $96.5 |
Average amount outstanding (based on daily outstanding balances) |  | $100.2 |  |  |  | $28.7 |  |  |  | $7.2 |  |  |  | $7.1 |  |  |  | $13.3 |  |  |  | $23.0 |
Weighted average interest rates | 0.4 | % |  | 0.3 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | 0.3 | %
(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, 2012. Refer to Note 7(b) for further discussion of $50 million of commercial paper outstanding at September 30, 2012 classified as long-term debt.
(b) Long-term Debt - In September 2012, Corporate Services issued $75 million of 3.45% senior notes due 2022. The proceeds from the September 2012 issuance were used by Corporate Services to repay short-term debt primarily incurred for the purchase of the corporate headquarters building and for general working capital purposes. As of September 30, 2012, $50 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s Condensed Consolidated 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 September 30, 2012, this commercial paper balance had a weighted average remaining maturity of 2 days and a 0.4% interest rate.
IPL [Member] |
Debt Instrument [Line Items] |
Debt | DEBT (a) Short-term Debt - Information regarding commercial paper issued under Alliant Energy’s, IPL’s and WPL’s credit facilities classified as short-term debt was as follows (dollars in millions):
| Alliant Energy |  | Parent |  |  |  |
September 30, 2012 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $70.4 |  | $70.4 |  | $— |  | $—
Remaining maturity | 1 day |  | 1 day |  | N/A |  | N/A
Interest rates | 0.4% |  | 0.4% |  | N/A |  | N/A
Available credit facility capacity (a) | $879.6 |  | $229.6 |  | $250.0 |  | $400.0
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $22.1 |  |  |  | $19.5 |  |  |  | $18.0 |  |  |  | $35.6 |  |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $133.0 |  |  |  | $2.6 |  |  |  | $1.3 |  |  |  | $1.7 |  |  |  | $11.9 |  |  |  | $— |
Weighted average interest rates | 0.4 | % |  | 0.4 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | N/A |
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $96.5 |  |  |  | $35.4 |  |  |  | $54.4 |  |  |  | $35.6 |  |  |  | $96.5 |
Average amount outstanding (based on daily outstanding balances) |  | $100.2 |  |  |  | $28.7 |  |  |  | $7.2 |  |  |  | $7.1 |  |  |  | $13.3 |  |  |  | $23.0 |
Weighted average interest rates | 0.4 | % |  | 0.3 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | 0.3 | %
(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, 2012. Refer to Note 7(b) for further discussion of $50 million of commercial paper outstanding at September 30, 2012 classified as long-term debt.
(b) Long-term Debt - In September 2012, Corporate Services issued $75 million of 3.45% senior notes due 2022. The proceeds from the September 2012 issuance were used by Corporate Services to repay short-term debt primarily incurred for the purchase of the corporate headquarters building and for general working capital purposes. As of September 30, 2012, $50 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s Condensed Consolidated 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 September 30, 2012, this commercial paper balance had a weighted average remaining maturity of 2 days and a 0.4% interest rate.
WPL [Member] |
Debt Instrument [Line Items] |
Debt | DEBT (a) Short-term Debt - Information regarding commercial paper issued under Alliant Energy’s, IPL’s and WPL’s credit facilities classified as short-term debt was as follows (dollars in millions):
| Alliant Energy |  | Parent |  |  |  |
September 30, 2012 | (Consolidated) |  | Company |  | IPL |  | WPL
Commercial paper: |  |  |  |  |  |  |
Amount outstanding | $70.4 |  | $70.4 |  | $— |  | $—
Remaining maturity | 1 day |  | 1 day |  | N/A |  | N/A
Interest rates | 0.4% |  | 0.4% |  | N/A |  | N/A
Available credit facility capacity (a) | $879.6 |  | $229.6 |  | $250.0 |  | $400.0
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $22.1 |  |  |  | $19.5 |  |  |  | $18.0 |  |  |  | $35.6 |  |  |  | $— |
Average amount outstanding (based on daily outstanding balances) |  | $133.0 |  |  |  | $2.6 |  |  |  | $1.3 |  |  |  | $1.7 |  |  |  | $11.9 |  |  |  | $— |
Weighted average interest rates | 0.4 | % |  | 0.4 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | N/A |
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) |  | $185.3 |  |  |  | $96.5 |  |  |  | $35.4 |  |  |  | $54.4 |  |  |  | $35.6 |  |  |  | $96.5 |
Average amount outstanding (based on daily outstanding balances) |  | $100.2 |  |  |  | $28.7 |  |  |  | $7.2 |  |  |  | $7.1 |  |  |  | $13.3 |  |  |  | $23.0 |
Weighted average interest rates | 0.4 | % |  | 0.3 | % |  | 0.4 | % |  | 0.3 | % |  | 0.3 | % |  | 0.3 | %
(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, 2012. Refer to Note 7(b) for further discussion of $50 million of commercial paper outstanding at September 30, 2012 classified as long-term debt.
(b) Long-term Debt - In September 2012, Corporate Services issued $75 million of 3.45% senior notes due 2022. The proceeds from the September 2012 issuance were used by Corporate Services to repay short-term debt primarily incurred for the purchase of the corporate headquarters building and for general working capital purposes. As of September 30, 2012, $50 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s Condensed Consolidated 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 September 30, 2012, this commercial paper balance had a weighted average remaining maturity of 2 days and a 0.4% interest rate.

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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 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 Reference 4: 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 + Details
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