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v2.4.1.9

Condensed Consolidated Statements Of Income (USD $) In Millions, except Per Share data, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2015 | Mar. 31, 2014
Utility: |  |
Electric | $ 671.3 us-gaap_ElectricDomesticRegulatedRevenue | $ 675.8 us-gaap_ElectricDomesticRegulatedRevenue
Gas | 198.4 us-gaap_GasDomesticRegulatedRevenue | 240.7 us-gaap_GasDomesticRegulatedRevenue
Other | 16.4 us-gaap_OtherSalesRevenueNet | 22.8 us-gaap_OtherSalesRevenueNet
Non-regulated | 11.3 us-gaap_UnregulatedOperatingRevenue | 13.5 us-gaap_UnregulatedOperatingRevenue
Total operating revenues | 897.4 us-gaap_Revenues | 952.8 us-gaap_Revenues
Utility: |  |
Electric production fuel and purchased power | 215.9 us-gaap_ElectricProductionExpense | 238.7 us-gaap_ElectricProductionExpense
Electric transmission service | 123.2 us-gaap_CostOfTransmission | 114.1 us-gaap_CostOfTransmission
Cost of gas sold | 130.8 us-gaap_CostOfDomesticRegulatedGasRevenue | 161.9 us-gaap_CostOfDomesticRegulatedGasRevenue
Other operation and maintenance | 146.6 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations | 161.0 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations
Non-regulated operation and maintenance | 1.3 us-gaap_OtherCostAndExpenseOperating | 1.3 us-gaap_OtherCostAndExpenseOperating
Depreciation and amortization | 100.2 us-gaap_DepreciationAndAmortization | 95.5 us-gaap_DepreciationAndAmortization
Taxes other than income taxes | 26.5 us-gaap_TaxesExcludingIncomeAndExciseTaxes | 26.1 us-gaap_TaxesExcludingIncomeAndExciseTaxes
Total operating expenses | 744.5 us-gaap_CostsAndExpenses | 798.6 us-gaap_CostsAndExpenses
Operating income | 152.9 us-gaap_OperatingIncomeLoss | 154.2 us-gaap_OperatingIncomeLoss
Interest expense and other: |  |
Interest expense | 46.6 us-gaap_InterestExpense | 45.2 us-gaap_InterestExpense
Equity income from unconsolidated investments, net | (6.5)us-gaap_IncomeLossFromEquityMethodInvestments | (11.4)us-gaap_IncomeLossFromEquityMethodInvestments
Allowance for funds used during construction | (6.8)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions | (9.1)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions
Interest income and other | (0.1)us-gaap_OtherNonoperatingIncomeExpense | (1.7)us-gaap_OtherNonoperatingIncomeExpense
Total interest expense and other | 33.2 us-gaap_NonoperatingIncomeExpense | 23.0 us-gaap_NonoperatingIncomeExpense
Income before income taxes | 119.7 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest | 131.2 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income tax expense (benefit) | 20.5 us-gaap_IncomeTaxExpenseBenefit | 20.6 us-gaap_IncomeTaxExpenseBenefit
Net income (loss) | 99.2 us-gaap_NetIncomeLoss | 110.6 us-gaap_NetIncomeLoss
Preferred dividend requirements of IPL | 2.6 us-gaap_DividendsPreferredStock | 2.6 us-gaap_DividendsPreferredStock
Net income (loss) attributable to common shareowners | 96.6 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | 108.0 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Weighted average number of common shares outstanding (basic and diluted) (in shares) | 111.1 us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted | 110.8 us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted) (in dollars per share) | $ 0.87 us-gaap_EarningsPerShareBasicAndDiluted | $ 0.97 us-gaap_EarningsPerShareBasicAndDiluted
Dividends declared per common share (in dollars per share) | $ 0.55 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.51 us-gaap_CommonStockDividendsPerShareDeclared
IPL [Member] |  |
Utility: |  |
Electric | 362.6 us-gaap_ElectricDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_IplMember | 374.2 us-gaap_ElectricDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_IplMember
Gas | 111.2 us-gaap_GasDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_IplMember | 135.7 us-gaap_GasDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_IplMember
Other | 15.2 us-gaap_OtherSalesRevenueNet / dei_LegalEntityAxis = lnt_IplMember | 19.0 us-gaap_OtherSalesRevenueNet / dei_LegalEntityAxis = lnt_IplMember
Total operating revenues | 489.0 us-gaap_Revenues / dei_LegalEntityAxis = lnt_IplMember | 528.9 us-gaap_Revenues / dei_LegalEntityAxis = lnt_IplMember
Utility: |  |
Electric production fuel and purchased power | 110.1 us-gaap_ElectricProductionExpense / dei_LegalEntityAxis = lnt_IplMember | 140.0 us-gaap_ElectricProductionExpense / dei_LegalEntityAxis = lnt_IplMember
Electric transmission service | 83.9 us-gaap_CostOfTransmission / dei_LegalEntityAxis = lnt_IplMember | 83.6 us-gaap_CostOfTransmission / dei_LegalEntityAxis = lnt_IplMember
Cost of gas sold | 71.0 us-gaap_CostOfDomesticRegulatedGasRevenue / dei_LegalEntityAxis = lnt_IplMember | 88.1 us-gaap_CostOfDomesticRegulatedGasRevenue / dei_LegalEntityAxis = lnt_IplMember
Other operation and maintenance | 92.6 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations / dei_LegalEntityAxis = lnt_IplMember | 97.2 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations / dei_LegalEntityAxis = lnt_IplMember
Depreciation and amortization | 51.8 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = lnt_IplMember | 48.7 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = lnt_IplMember
Taxes other than income taxes | 14.1 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = lnt_IplMember | 13.8 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = lnt_IplMember
Total operating expenses | 423.5 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = lnt_IplMember | 471.4 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = lnt_IplMember
Operating income | 65.5 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = lnt_IplMember | 57.5 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = lnt_IplMember
Interest expense and other: |  |
Interest expense | 24.1 us-gaap_InterestExpense / dei_LegalEntityAxis = lnt_IplMember | 22.5 us-gaap_InterestExpense / dei_LegalEntityAxis = lnt_IplMember
Allowance for funds used during construction | (5.3)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions / dei_LegalEntityAxis = lnt_IplMember | (6.0)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions / dei_LegalEntityAxis = lnt_IplMember
Interest income and other | (0.1)us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_IplMember | 0 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_IplMember
Total interest expense and other | 18.7 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_IplMember | 16.5 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_IplMember
Income before income taxes | 46.8 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = lnt_IplMember | 41.0 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = lnt_IplMember
Income tax expense (benefit) | (3.6)us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = lnt_IplMember | (5.0)us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = lnt_IplMember
Net income (loss) | 50.4 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = lnt_IplMember | 46.0 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = lnt_IplMember
Preferred dividend requirements of IPL | 2.6 us-gaap_DividendsPreferredStock / dei_LegalEntityAxis = lnt_IplMember | 2.6 us-gaap_DividendsPreferredStock / dei_LegalEntityAxis = lnt_IplMember
Net income (loss) attributable to common shareowners | 47.8 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = lnt_IplMember | 43.4 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = lnt_IplMember
WPL [Member] |  |
Utility: |  |
Electric | 308.7 us-gaap_ElectricDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_WplMember | 301.6 us-gaap_ElectricDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_WplMember
Gas | 87.2 us-gaap_GasDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_WplMember | 105.0 us-gaap_GasDomesticRegulatedRevenue / dei_LegalEntityAxis = lnt_WplMember
Other | 1.2 us-gaap_OtherSalesRevenueNet / dei_LegalEntityAxis = lnt_WplMember | 3.8 us-gaap_OtherSalesRevenueNet / dei_LegalEntityAxis = lnt_WplMember
Total operating revenues | 397.1 us-gaap_Revenues / dei_LegalEntityAxis = lnt_WplMember | 410.4 us-gaap_Revenues / dei_LegalEntityAxis = lnt_WplMember
Utility: |  |
Electric production fuel and purchased power | 105.8 us-gaap_ElectricProductionExpense / dei_LegalEntityAxis = lnt_WplMember | 98.7 us-gaap_ElectricProductionExpense / dei_LegalEntityAxis = lnt_WplMember
Electric transmission service | 39.3 us-gaap_CostOfTransmission / dei_LegalEntityAxis = lnt_WplMember | 30.5 us-gaap_CostOfTransmission / dei_LegalEntityAxis = lnt_WplMember
Cost of gas sold | 59.8 us-gaap_CostOfDomesticRegulatedGasRevenue / dei_LegalEntityAxis = lnt_WplMember | 73.8 us-gaap_CostOfDomesticRegulatedGasRevenue / dei_LegalEntityAxis = lnt_WplMember
Other operation and maintenance | 54.0 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations / dei_LegalEntityAxis = lnt_WplMember | 63.8 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations / dei_LegalEntityAxis = lnt_WplMember
Depreciation and amortization | 46.0 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = lnt_WplMember | 44.7 us-gaap_DepreciationAndAmortization / dei_LegalEntityAxis = lnt_WplMember
Taxes other than income taxes | 11.4 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = lnt_WplMember | 11.2 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = lnt_WplMember
Total operating expenses | 316.3 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = lnt_WplMember | 322.7 us-gaap_CostsAndExpenses / dei_LegalEntityAxis = lnt_WplMember
Operating income | 80.8 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = lnt_WplMember | 87.7 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = lnt_WplMember
Interest expense and other: |  |
Interest expense | 23.1 us-gaap_InterestExpense / dei_LegalEntityAxis = lnt_WplMember | 21.1 us-gaap_InterestExpense / dei_LegalEntityAxis = lnt_WplMember
Equity income from unconsolidated investments, net | (7.8)us-gaap_IncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = lnt_WplMember | (11.4)us-gaap_IncomeLossFromEquityMethodInvestments / dei_LegalEntityAxis = lnt_WplMember
Allowance for funds used during construction | (1.5)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions / dei_LegalEntityAxis = lnt_WplMember | (3.1)us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions / dei_LegalEntityAxis = lnt_WplMember
Interest income and other | 0.1 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_WplMember | 0 us-gaap_OtherNonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_WplMember
Total interest expense and other | 13.9 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_WplMember | 6.6 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = lnt_WplMember
Income before income taxes | 66.9 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = lnt_WplMember | 81.1 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = lnt_WplMember
Income tax expense (benefit) | 22.1 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = lnt_WplMember | 26.3 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = lnt_WplMember
Net income (loss) | 44.8 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = lnt_WplMember | 54.8 us-gaap_NetIncomeLoss / dei_LegalEntityAxis = lnt_WplMember
Net income attributable to noncontrolling interest | 0.2 us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / dei_LegalEntityAxis = lnt_WplMember | 0 us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / dei_LegalEntityAxis = lnt_WplMember
Net income (loss) attributable to common shareowners | $ 44.6 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = lnt_WplMember | $ 54.8 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = lnt_WplMember

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