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Derivative Instruments (Tables) | 3 Months Ended
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Mar. 31, 2013
Derivative [Line Items] |
Notional Amounts Of Derivative Instruments | As of March 31, 2013, notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):
| 2013 |  | 2014 |  | 2015 |  | 2016 |  | Total
Alliant Energy |  |  |  |  |  |  |  |  |
Electricity (megawatt-hours (MWhs)) | 3,431 |  |  | 3,164 |  |  | 876 |  |  | — |  |  | 7,471 |
FTRs (MWs) | 11 |  |  | — |  |  | — |  |  | — |  |  | 11 |
Natural gas (dekatherms (Dths)) | 66,884 |  |  | 10,130 |  |  | 1,880 |  |  | 455 |  |  | 79,349 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
IPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,987 |  |  | 1,024 |  |  | — |  |  | — |  |  | 3,011 |
FTRs (MWs) | 6 |  |  | — |  |  | — |  |  | — |  |  | 6 |
Natural gas (Dths) | 52,116 |  |  | 5,765 |  |  | 1,430 |  |  | 455 |  |  | 59,766 |
WPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,444 |  |  | 2,140 |  |  | 876 |  |  | — |  |  | 4,460 |
FTRs (MWs) | 5 |  |  | — |  |  | — |  |  | — |  |  | 5 |
Natural gas (Dths) | 14,768 |  |  | 4,365 |  |  | 450 |  |  | — |  |  | 19,583 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
Fair Value Of Financial Instruments | The fair values of current derivative assets were included in “Other current assets,” non-current derivative assets were included in “Deferred charges and other,” current derivative liabilities were included in “Other current liabilities” and non-current derivative liabilities were included in “Other long-term liabilities and deferred credits” on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Commodity contracts | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012
Current derivative assets |  | $17.5 |  |  |  | $23.5 |  |  |  | $10.9 |  |  |  | $17.0 |  |  |  | $6.6 |  |  |  | $6.5 |
Non-current derivative assets | 6.1 |  |  | 2.7 |  |  | 1.6 |  |  | 0.5 |  |  | 4.5 |  |  | 2.2 |
Current derivative liabilities | 13.5 |  |  | 31.1 |  |  | 5.7 |  |  | 14.1 |  |  | 7.8 |  |  | 17.0 |
Non-current derivative liabilities | 3.6 |  |  | 9.3 |  |  | 0.4 |  |  | 2.0 |  |  | 3.2 |  |  | 7.3 |
Gains And Losses From Derivative Instruments Not Designated As Hedging Instruments | Changes in unrealized gains (losses) from commodity derivative instruments not designated as hedging instruments were recorded with offsets to regulatory assets or regulatory liabilities on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2013 |  | 2012 |  | 2013 |  | 2012 |  | 2013 |  | 2012
Three Months Ended March 31 |  |  |  |  |  |  |  |  |  |  |
Regulatory assets |  | $9.5 |  |  |  | ($39.7 | ) |  |  | $2.7 |  |  |  | ($22.2 | ) |  |  | $6.8 |  |  |  | ($17.5 | )
Regulatory liabilities | 16.4 |  |  | 1.4 |  |  | 8.8 |  |  | — |  |  | 7.6 |  |  | 1.4 |
Balance Sheet Offsetting | Alliant Energy, IPL and WPL do not net derivative instruments subject to a master netting arrangement by counterparty on the Condensed Consolidated Balance Sheets. Alliant Energy, IPL and WPL also do not offset fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. However, if Alliant Energy, IPL and WPL did net derivative instruments and related cash collateral by counterparty, derivative assets and derivative liabilities related to commodity contracts would have been presented on their Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| Gross |  |  |  | Gross |  |  |  | Gross |  |
| (as reported) |  | Net |  | (as reported) |  | Net |  | (as reported) |  | Net
March 31, 2013 |  |  |  |  |  |  |  |  |  |  |
Derivative assets |  | $23.6 |  |  |  | $16.3 |  |  |  | $12.5 |  |  |  | $9.0 |  |  |  | $11.1 |  |  |  | $7.3 |
Derivative liabilities | 17.1 |  |  | 9.8 |  |  | 6.1 |  |  | 2.6 |  |  | 11.0 |  |  | 7.2 |
December 31, 2012 |  |  |  |  |  |  |  |  |  |  |
Derivative assets | 26.2 |  |  | 19.3 |  |  | 17.5 |  |  | 14.5 |  |  | 8.7 |  |  | 4.8 |
Derivative liabilities | 40.4 |  |  | 33.0 |  |  | 16.1 |  |  | 12.6 |  |  | 24.3 |  |  | 20.4 |
IPL [Member] |
Derivative [Line Items] |
Notional Amounts Of Derivative Instruments | As of March 31, 2013, notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):
| 2013 |  | 2014 |  | 2015 |  | 2016 |  | Total
Alliant Energy |  |  |  |  |  |  |  |  |
Electricity (megawatt-hours (MWhs)) | 3,431 |  |  | 3,164 |  |  | 876 |  |  | — |  |  | 7,471 |
FTRs (MWs) | 11 |  |  | — |  |  | — |  |  | — |  |  | 11 |
Natural gas (dekatherms (Dths)) | 66,884 |  |  | 10,130 |  |  | 1,880 |  |  | 455 |  |  | 79,349 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
IPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,987 |  |  | 1,024 |  |  | — |  |  | — |  |  | 3,011 |
FTRs (MWs) | 6 |  |  | — |  |  | — |  |  | — |  |  | 6 |
Natural gas (Dths) | 52,116 |  |  | 5,765 |  |  | 1,430 |  |  | 455 |  |  | 59,766 |
WPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,444 |  |  | 2,140 |  |  | 876 |  |  | — |  |  | 4,460 |
FTRs (MWs) | 5 |  |  | — |  |  | — |  |  | — |  |  | 5 |
Natural gas (Dths) | 14,768 |  |  | 4,365 |  |  | 450 |  |  | — |  |  | 19,583 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
Fair Value Of Financial Instruments | The fair values of current derivative assets were included in “Other current assets,” non-current derivative assets were included in “Deferred charges and other,” current derivative liabilities were included in “Other current liabilities” and non-current derivative liabilities were included in “Other long-term liabilities and deferred credits” on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Commodity contracts | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012
Current derivative assets |  | $17.5 |  |  |  | $23.5 |  |  |  | $10.9 |  |  |  | $17.0 |  |  |  | $6.6 |  |  |  | $6.5 |
Non-current derivative assets | 6.1 |  |  | 2.7 |  |  | 1.6 |  |  | 0.5 |  |  | 4.5 |  |  | 2.2 |
Current derivative liabilities | 13.5 |  |  | 31.1 |  |  | 5.7 |  |  | 14.1 |  |  | 7.8 |  |  | 17.0 |
Non-current derivative liabilities | 3.6 |  |  | 9.3 |  |  | 0.4 |  |  | 2.0 |  |  | 3.2 |  |  | 7.3 |
Gains And Losses From Derivative Instruments Not Designated As Hedging Instruments | Changes in unrealized gains (losses) from commodity derivative instruments not designated as hedging instruments were recorded with offsets to regulatory assets or regulatory liabilities on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2013 |  | 2012 |  | 2013 |  | 2012 |  | 2013 |  | 2012
Three Months Ended March 31 |  |  |  |  |  |  |  |  |  |  |
Regulatory assets |  | $9.5 |  |  |  | ($39.7 | ) |  |  | $2.7 |  |  |  | ($22.2 | ) |  |  | $6.8 |  |  |  | ($17.5 | )
Regulatory liabilities | 16.4 |  |  | 1.4 |  |  | 8.8 |  |  | — |  |  | 7.6 |  |  | 1.4 |
Balance Sheet Offsetting | Alliant Energy, IPL and WPL do not net derivative instruments subject to a master netting arrangement by counterparty on the Condensed Consolidated Balance Sheets. Alliant Energy, IPL and WPL also do not offset fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. However, if Alliant Energy, IPL and WPL did net derivative instruments and related cash collateral by counterparty, derivative assets and derivative liabilities related to commodity contracts would have been presented on their Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| Gross |  |  |  | Gross |  |  |  | Gross |  |
| (as reported) |  | Net |  | (as reported) |  | Net |  | (as reported) |  | Net
March 31, 2013 |  |  |  |  |  |  |  |  |  |  |
Derivative assets |  | $23.6 |  |  |  | $16.3 |  |  |  | $12.5 |  |  |  | $9.0 |  |  |  | $11.1 |  |  |  | $7.3 |
Derivative liabilities | 17.1 |  |  | 9.8 |  |  | 6.1 |  |  | 2.6 |  |  | 11.0 |  |  | 7.2 |
December 31, 2012 |  |  |  |  |  |  |  |  |  |  |
Derivative assets | 26.2 |  |  | 19.3 |  |  | 17.5 |  |  | 14.5 |  |  | 8.7 |  |  | 4.8 |
Derivative liabilities | 40.4 |  |  | 33.0 |  |  | 16.1 |  |  | 12.6 |  |  | 24.3 |  |  | 20.4 |
WPL [Member] |
Derivative [Line Items] |
Notional Amounts Of Derivative Instruments | As of March 31, 2013, notional amounts by delivery year related to outstanding swap contracts, option contracts, physical forward contracts, FTRs and coal contracts that were accounted for as commodity derivative instruments were as follows (units in thousands):
| 2013 |  | 2014 |  | 2015 |  | 2016 |  | Total
Alliant Energy |  |  |  |  |  |  |  |  |
Electricity (megawatt-hours (MWhs)) | 3,431 |  |  | 3,164 |  |  | 876 |  |  | — |  |  | 7,471 |
FTRs (MWs) | 11 |  |  | — |  |  | — |  |  | — |  |  | 11 |
Natural gas (dekatherms (Dths)) | 66,884 |  |  | 10,130 |  |  | 1,880 |  |  | 455 |  |  | 79,349 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
IPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,987 |  |  | 1,024 |  |  | — |  |  | — |  |  | 3,011 |
FTRs (MWs) | 6 |  |  | — |  |  | — |  |  | — |  |  | 6 |
Natural gas (Dths) | 52,116 |  |  | 5,765 |  |  | 1,430 |  |  | 455 |  |  | 59,766 |
WPL |  |  |  |  |  |  |  |  |
Electricity (MWhs) | 1,444 |  |  | 2,140 |  |  | 876 |  |  | — |  |  | 4,460 |
FTRs (MWs) | 5 |  |  | — |  |  | — |  |  | — |  |  | 5 |
Natural gas (Dths) | 14,768 |  |  | 4,365 |  |  | 450 |  |  | — |  |  | 19,583 |
Coal (tons) | 672 |  |  | 981 |  |  | 562 |  |  | — |  |  | 2,215 |
Fair Value Of Financial Instruments | The fair values of current derivative assets were included in “Other current assets,” non-current derivative assets were included in “Deferred charges and other,” current derivative liabilities were included in “Other current liabilities” and non-current derivative liabilities were included in “Other long-term liabilities and deferred credits” on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Commodity contracts | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012 |  | March 31, 2013 |  | December 31, 2012
Current derivative assets |  | $17.5 |  |  |  | $23.5 |  |  |  | $10.9 |  |  |  | $17.0 |  |  |  | $6.6 |  |  |  | $6.5 |
Non-current derivative assets | 6.1 |  |  | 2.7 |  |  | 1.6 |  |  | 0.5 |  |  | 4.5 |  |  | 2.2 |
Current derivative liabilities | 13.5 |  |  | 31.1 |  |  | 5.7 |  |  | 14.1 |  |  | 7.8 |  |  | 17.0 |
Non-current derivative liabilities | 3.6 |  |  | 9.3 |  |  | 0.4 |  |  | 2.0 |  |  | 3.2 |  |  | 7.3 |
Gains And Losses From Derivative Instruments Not Designated As Hedging Instruments | Changes in unrealized gains (losses) from commodity derivative instruments not designated as hedging instruments were recorded with offsets to regulatory assets or regulatory liabilities on the Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2013 |  | 2012 |  | 2013 |  | 2012 |  | 2013 |  | 2012
Three Months Ended March 31 |  |  |  |  |  |  |  |  |  |  |
Regulatory assets |  | $9.5 |  |  |  | ($39.7 | ) |  |  | $2.7 |  |  |  | ($22.2 | ) |  |  | $6.8 |  |  |  | ($17.5 | )
Regulatory liabilities | 16.4 |  |  | 1.4 |  |  | 8.8 |  |  | — |  |  | 7.6 |  |  | 1.4 |
Balance Sheet Offsetting | Alliant Energy, IPL and WPL do not net derivative instruments subject to a master netting arrangement by counterparty on the Condensed Consolidated Balance Sheets. Alliant Energy, IPL and WPL also do not offset fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. However, if Alliant Energy, IPL and WPL did net derivative instruments and related cash collateral by counterparty, derivative assets and derivative liabilities related to commodity contracts would have been presented on their Condensed Consolidated Balance Sheets as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| Gross |  |  |  | Gross |  |  |  | Gross |  |
| (as reported) |  | Net |  | (as reported) |  | Net |  | (as reported) |  | Net
March 31, 2013 |  |  |  |  |  |  |  |  |  |  |
Derivative assets |  | $23.6 |  |  |  | $16.3 |  |  |  | $12.5 |  |  |  | $9.0 |  |  |  | $11.1 |  |  |  | $7.3 |
Derivative liabilities | 17.1 |  |  | 9.8 |  |  | 6.1 |  |  | 2.6 |  |  | 11.0 |  |  | 7.2 |
December 31, 2012 |  |  |  |  |  |  |  |  |  |  |
Derivative assets | 26.2 |  |  | 19.3 |  |  | 17.5 |  |  | 14.5 |  |  | 8.7 |  |  | 4.8 |
Derivative liabilities | 40.4 |  |  | 33.0 |  |  | 16.1 |  |  | 12.6 |  |  | 24.3 |  |  | 20.4 |

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- Definition Tabular disclosure of the location and amount of gains and losses reported in the statement of financial performance, or when applicable, the statement of financial position. For example, (a) gains and losses recognized in the income statement on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges and (b) gains and losses initially recognized in other comprehensive income on derivative instruments designated and qualifying as cash flow hedges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -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 FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph b -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph a -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. + Details
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- Definition Tabular disclosure of the notional amounts of outstanding derivative positions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 + Details
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