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v2.4.1.9

Consolidated Statements Of Income (USD $) In Millions, except Per Share data, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2015 | Mar. 31, 2014
Operating Revenue | $ 2,111 us-gaap_Revenues | $ 2,523 us-gaap_Revenues
Operating Expenses |  |
Fuel for electric generation | 167 us-gaap_FuelCosts | 219 us-gaap_FuelCosts
Purchased and interchange power | 349 us-gaap_UtilitiesOperatingExpensePurchasedPower | 498 us-gaap_UtilitiesOperatingExpensePurchasedPower
Purchased power - related parties | 23 cms_PurchasedPowerRelatedParties | 24 cms_PurchasedPowerRelatedParties
Cost of gas sold | 589 us-gaap_CostOfNaturalGasPurchases | 834 us-gaap_CostOfNaturalGasPurchases
Maintenance and other operating expenses | 283 us-gaap_OtherCostAndExpenseOperating | 266 us-gaap_OtherCostAndExpenseOperating
Depreciation and amortization | 222 us-gaap_DepreciationDepletionAndAmortization | 199 us-gaap_DepreciationDepletionAndAmortization
General taxes | 81 us-gaap_TaxesExcludingIncomeAndExciseTaxes | 75 us-gaap_TaxesExcludingIncomeAndExciseTaxes
Total operating expenses | 1,714 us-gaap_OperatingExpenses | 2,115 us-gaap_OperatingExpenses
Operating Income | 397 us-gaap_OperatingIncomeLoss | 408 us-gaap_OperatingIncomeLoss
Other Income (Expense) |  |
Interest income | 1 us-gaap_InvestmentIncomeInterestAndDividend |
Allowance for equity funds used during construction | 2 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity | 2 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity
Income from equity method investees | 4 us-gaap_IncomeLossFromEquityMethodInvestments | 4 us-gaap_IncomeLossFromEquityMethodInvestments
Other income | 3 us-gaap_OtherNonoperatingIncome | 3 us-gaap_OtherNonoperatingIncome
Other expense | (4)us-gaap_OtherNonoperatingExpense | (7)us-gaap_OtherNonoperatingExpense
Total other income (expense) | 6 us-gaap_NonoperatingIncomeExpense | 2 us-gaap_NonoperatingIncomeExpense
Interest Charges |  |
Interest on long-term debt | 96 us-gaap_InterestExpenseDebt | 97 us-gaap_InterestExpenseDebt
Other interest expense | 6 us-gaap_InterestExpenseOther | 5 us-gaap_InterestExpenseOther
Allowance for borrowed funds used during construction | (1)us-gaap_InterestCostsCapitalizedAdjustment | (1)us-gaap_InterestCostsCapitalizedAdjustment
Total interest charges | 101 us-gaap_InterestExpense | 101 us-gaap_InterestExpense
Income Before Income Taxes | 302 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest | 309 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income Tax Expense | 100 us-gaap_IncomeTaxExpenseBenefit | 105 us-gaap_IncomeTaxExpenseBenefit
Net Income | 202 us-gaap_ProfitLoss | 204 us-gaap_ProfitLoss
Basic Earnings Per Average Common Share | $ 0.73 us-gaap_EarningsPerShareBasic | $ 0.77 us-gaap_EarningsPerShareBasic
Diluted Earnings Per Average Common Share | $ 0.73 us-gaap_EarningsPerShareDiluted | $ 0.75 us-gaap_EarningsPerShareDiluted
Dividends declared per common share | $ 0.29 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.27 us-gaap_CommonStockDividendsPerShareDeclared
Consumers Energy Company [Member] |  |
Operating Revenue | 2,028 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 2,382 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Operating Expenses |  |
Fuel for electric generation | 133 us-gaap_FuelCosts / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 186 us-gaap_FuelCosts / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Purchased and interchange power | 346 us-gaap_UtilitiesOperatingExpensePurchasedPower / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 484 us-gaap_UtilitiesOperatingExpensePurchasedPower / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Purchased power - related parties | 23 cms_PurchasedPowerRelatedParties / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 24 cms_PurchasedPowerRelatedParties / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Cost of gas sold | 583 us-gaap_CostOfNaturalGasPurchases / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 768 us-gaap_CostOfNaturalGasPurchases / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Maintenance and other operating expenses | 265 us-gaap_OtherCostAndExpenseOperating / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 250 us-gaap_OtherCostAndExpenseOperating / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Depreciation and amortization | 220 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 197 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
General taxes | 79 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 74 us-gaap_TaxesExcludingIncomeAndExciseTaxes / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Total operating expenses | 1,649 us-gaap_OperatingExpenses / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 1,983 us-gaap_OperatingExpenses / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Operating Income | 379 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 399 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Other Income (Expense) |  |
Interest income | 1 us-gaap_InvestmentIncomeInterestAndDividend / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Allowance for equity funds used during construction | 2 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 2 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Other income | 12 us-gaap_OtherNonoperatingIncome / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 3 us-gaap_OtherNonoperatingIncome / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Other expense | (4)us-gaap_OtherNonoperatingExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | (6)us-gaap_OtherNonoperatingExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Total other income (expense) | 11 us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | (1)us-gaap_NonoperatingIncomeExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Interest Charges |  |
Interest on long-term debt | 63 us-gaap_InterestExpenseDebt / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 59 us-gaap_InterestExpenseDebt / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Other interest expense | 3 us-gaap_InterestExpenseOther / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 3 us-gaap_InterestExpenseOther / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Allowance for borrowed funds used during construction | (1)us-gaap_InterestCostsCapitalizedAdjustment / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | (1)us-gaap_InterestCostsCapitalizedAdjustment / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Total interest charges | 65 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 61 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Income Before Income Taxes | 325 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 337 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Income Tax Expense | 110 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 116 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember
Net Income | $ 215 us-gaap_ProfitLoss / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | $ 221 us-gaap_ProfitLoss / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember

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