XML 44 R118.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Reportable Segments (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue | $ 1,758 us-gaap_Revenues |  | $ 1,430 us-gaap_Revenues | $ 1,468 us-gaap_Revenues | $ 2,523 us-gaap_Revenues | $ 1,736 us-gaap_Revenues |  | $ 1,445 us-gaap_Revenues | $ 1,406 us-gaap_Revenues | $ 1,979 us-gaap_Revenues | $ 7,179 us-gaap_Revenues |  | $ 6,566 us-gaap_Revenues |  | $ 6,253 us-gaap_Revenues |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 685 us-gaap_DepreciationDepletionAndAmortization |  | 628 us-gaap_DepreciationDepletionAndAmortization |  | 598 us-gaap_DepreciationDepletionAndAmortization |
Income (loss) from equity method investees |  |  |  |  |  |  |  |  |  |  | 15 us-gaap_IncomeLossFromEquityMethodInvestments |  | 13 us-gaap_IncomeLossFromEquityMethodInvestments |  | 17 us-gaap_IncomeLossFromEquityMethodInvestments |
Interest charges |  |  |  |  |  |  |  |  |  |  | 407 us-gaap_InterestExpense |  | 398 us-gaap_InterestExpense |  | 389 us-gaap_InterestExpense |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 250 us-gaap_IncomeTaxExpenseBenefit |  | 302 us-gaap_IncomeTaxExpenseBenefit |  | 245 us-gaap_IncomeTaxExpenseBenefit |
Net Income Attributable to CMS Energy | 96 us-gaap_NetIncomeLoss |  | 94 us-gaap_NetIncomeLoss | 83 us-gaap_NetIncomeLoss | 204 us-gaap_NetIncomeLoss | 102 us-gaap_NetIncomeLoss |  | 126 us-gaap_NetIncomeLoss | 80 us-gaap_NetIncomeLoss | 144 us-gaap_NetIncomeLoss | 477 us-gaap_NetIncomeLoss |  | 452 us-gaap_NetIncomeLoss |  | 382 us-gaap_NetIncomeLoss |
Plant, property, and equipment, gross | 17,721 cms_PropertyPlantAndEquipmentGrossExcludingCWIP |  |  |  |  | 16,184 cms_PropertyPlantAndEquipmentGrossExcludingCWIP |  |  |  |  | 17,721 cms_PropertyPlantAndEquipmentGrossExcludingCWIP |  | 16,184 cms_PropertyPlantAndEquipmentGrossExcludingCWIP |  | 15,592 cms_PropertyPlantAndEquipmentGrossExcludingCWIP |
Investments in equity method investees | 61 us-gaap_EquityMethodInvestments | [1] |  |  |  | 59 us-gaap_EquityMethodInvestments | [1] |  |  |  | 61 us-gaap_EquityMethodInvestments | [1] | 59 us-gaap_EquityMethodInvestments | [1] | 57 us-gaap_EquityMethodInvestments | [1]
Total Assets | 19,185 us-gaap_Assets |  |  |  |  | 17,416 us-gaap_Assets |  |  |  |  | 19,185 us-gaap_Assets |  | 17,416 us-gaap_Assets |  | 17,131 us-gaap_Assets |
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 1,616 us-gaap_PaymentsToAcquireProductiveAssets | [2] | 1,408 us-gaap_PaymentsToAcquireProductiveAssets | [2] | 1,266 us-gaap_PaymentsToAcquireProductiveAssets | [2]
Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue | 1,672 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 1,359 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 1,387 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 2,382 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 1,674 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 1,386 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 1,342 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 1,919 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 6,800 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 6,321 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 6,013 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 678 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 622 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 592 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 250 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 245 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 244 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 306 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 346 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 297 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Net Income Available to Common Stockholders | 117 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 119 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 108 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 221 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 119 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 152 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 99 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 162 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember | 565 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 532 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 437 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Plant, property, and equipment, gross | 17,580 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  |  |  |  | 16,044 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  |  |  |  | 17,580 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 16,044 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 15,456 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Total Assets | 17,847 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  |  |  |  | 16,179 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  |  |  |  | 17,847 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 16,179 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 16,275 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 1,612 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 1,403 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |  | 1,261 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember |
Electric Utility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 4,436 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 4,173 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 4,031 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 522 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 484 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 459 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 181 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 179 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 179 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 211 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 242 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 227 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Net Income Attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  | 384 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 363 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 325 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Plant, property, and equipment, gross | 12,230 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  |  |  |  | 11,186 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  |  |  |  | 12,230 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 11,186 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 11,041 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Total Assets | 11,582 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] |  |  |  | 10,487 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] |  |  |  | 11,582 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] | 10,487 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] | 10,423 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3]
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 1,139 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 996 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 921 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Electric Utility [Member] | Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 4,436 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 4,173 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 4,031 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 522 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 484 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 459 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 181 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 179 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 179 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 211 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 242 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 227 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Net Income Available to Common Stockholders |  |  |  |  |  |  |  |  |  |  | 384 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 363 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 325 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Plant, property, and equipment, gross | 12,230 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  |  |  |  | 11,186 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  |  |  |  | 12,230 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 11,186 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 11,041 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Total Assets | 11,582 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] |  |  |  | 10,487 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] |  |  |  | 11,582 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] | 10,487 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3] | 10,423 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember | [3]
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 1,139 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 996 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |  | 921 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_ElectricUtilityMember |
Gas Utility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 2,363 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 2,148 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 1,982 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 156 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 138 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 133 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 67 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 64 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 63 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 95 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 104 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 70 us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Net Income Attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  | 179 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 168 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 110 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Plant, property, and equipment, gross | 5,335 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  |  |  |  | 4,843 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  |  |  |  | 5,335 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 4,843 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 4,400 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Total Assets | 5,391 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] |  |  |  | 4,784 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] |  |  |  | 5,391 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] | 4,784 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] | 5,016 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3]
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 473 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 407 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 340 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Gas Utility [Member] | Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 2,363 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 2,148 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 1,982 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 156 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 138 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 133 us-gaap_DepreciationDepletionAndAmortization / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 67 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 64 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 63 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | 95 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 104 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 70 us-gaap_IncomeTaxExpenseBenefit / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Net Income Available to Common Stockholders |  |  |  |  |  |  |  |  |  |  | 179 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 168 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 110 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Plant, property, and equipment, gross | 5,335 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  |  |  |  | 4,843 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  |  |  |  | 5,335 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 4,843 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |  | 4,400 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember |
Total Assets | 5,391 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] |  |  |  | 4,784 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] |  |  |  | 5,391 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] | 4,784 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3] | 5,016 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [3]
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 473 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [2] | 407 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [2] | 340 us-gaap_PaymentsToAcquireProductiveAssets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_GasUtilityMember | [2]
Enterprises [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 299 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 181 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 183 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 4 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 3 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 4 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Income (loss) from equity method investees |  |  |  |  |  |  |  |  |  |  | 15 us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [1] | 13 us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [1] | 17 us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [1]
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | (1)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | (4)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | (1)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Net Income Attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  | (1)us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 2 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 16 us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Plant, property, and equipment, gross | 115 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 115 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 115 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 115 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 113 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Investments in equity method investees | 58 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 57 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 58 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 57 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 55 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Total Assets | 231 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 332 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  |  |  |  | 231 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 332 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |  | 181 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember |
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 3 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [2] | 1 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [2] | 1 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_EnterprisesMember | [2]
Other [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 81 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 64 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 57 us-gaap_Revenues / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Depreciation and amortization |  |  |  |  |  |  |  |  |  |  | 3 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 3 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_DepreciationDepletionAndAmortization / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Interest charges |  |  |  |  |  |  |  |  |  |  | 159 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 155 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 147 us-gaap_InterestExpense / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Income tax expense (benefit) |  |  |  |  |  |  |  |  |  |  | (55)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | (40)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | (51)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Net Income Attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  | (85)us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | (81)us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | (69)us-gaap_NetIncomeLoss / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Plant, property, and equipment, gross | 41 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 40 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 41 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 40 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 38 cms_PropertyPlantAndEquipmentGrossExcludingCWIP / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Investments in equity method investees | 3 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 2 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 3 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_EquityMethodInvestments / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Total Assets | 1,981 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 1,813 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 1,981 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 1,813 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 1,511 us-gaap_Assets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Capital Expenditures |  |  |  |  |  |  |  |  |  |  | 1 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 4 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 4 us-gaap_PaymentsToAcquireProductiveAssets / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Other [Member] | Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 1 us-gaap_Revenues / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  |
Interest charges |  |  |  |  |  |  |  |  |  |  | 2 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_InterestExpense / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Net Income Available to Common Stockholders |  |  |  |  |  |  |  |  |  |  | 2 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 1 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 2 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Plant, property, and equipment, gross | 15 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 15 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | 15 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 15 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | 15 cms_PublicUtilitiesPropertyPlantAndEquipmentGrossExcludingCWIP / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
Total Assets | $ 874 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | $ 908 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  |  |  |  | $ 874 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | $ 908 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |  | $ 836 us-gaap_Assets / dei_LegalEntityAxis = cms_ConsumersEnergyCompanyMember / us-gaap_StatementOperatingActivitiesSegmentAxis = cms_OtherSegmentMember |
[1] | Consumers had no significant equity method investments.
[2] | Amounts include purchase of capital lease additions. Amounts also include a portion of Consumers’ capital expenditures for plant and equipment attributable to both the electric and gas utility businesses.
[3] | Amounts include a portion of Consumers’ other common assets attributable to both the electric and gas utility businesses.

X
- Definition Amount before accumulated depreciation, depletion and amortization and construction in progress of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References No definition available. + Details
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