XML 39 R8.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Consolidated Statements Of Changes In Equity - USD ($) shares in Thousands, $ in Millions | Consumers Energy Company [Member] CMS Energy Common Stock [Member] | Consumers Energy Company [Member] Other Paid-in Capital [Member] | Consumers Energy Company [Member] Accumulated Other Comprehensive Income (Loss) [Member] | Consumers Energy Company [Member] Retirement Benefits Liability [Member] | Consumers Energy Company [Member] Investments [Member] | Consumers Energy Company [Member] Retained Earnings (Accumulated Deficit) [Member] | Consumers Energy Company [Member] Preferred Stock [Member] | Consumers Energy Company [Member] | CMS Energy Common Stock [Member] | Other Paid-in Capital [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Retirement Benefits Liability [Member] | Investments [Member] | Derivative Instruments [Member] | Retained Earnings (Accumulated Deficit) [Member] | Noncontrolling Interest [Member] | Total
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Total Equity, beginning at Dec. 31, 2012 | $ 841 | $ 3,107 | $ (8) | $ (25) | $ 17 | $ 598 | $ 44 | $ 4,582 | $ 3 | $ 4,669 | $ (55) | $ (56) | $ 2 | $ (1) | $ (1,423) | $ 44 | $ 3,238
Beginning of period, shares at Dec. 31, 2012 |  |  |  |  |  |  |  |  | 264,072 |  |  |  |  |  |  |  |
Common stock issued |  |  |  |  |  |  |  |  |  | 51 |  |  |  |  |  |  |
Number of Shares Issued |  |  |  |  |  |  |  |  | 2,238 |  |  |  |  |  |  |  |
Common stock repurchased |  |  |  |  |  |  |  |  |  | (10) |  |  |  |  |  |  |
Common stock repurchased, shares |  |  |  |  |  |  |  |  | (356) |  |  |  |  |  |  |  |
Common stock reissued |  |  |  |  |  |  |  |  |  | $ 5 |  |  |  |  |  |  |
Common stock reissued, shares |  |  |  |  |  |  |  |  | 205 |  |  |  |  |  |  |  |
Conversion option on convertible debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reacquired, value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reacquired, shares |  |  |  |  |  |  |  |  | (22) |  |  |  |  |  |  |  |
Stockholder contribution |  | $ 150 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return of stockholder contribution |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain arising during the period |  |  |  | 5 |  |  |  | 5 |  |  |  | 26 |  |  |  |  | 26
Prior service credit adjustment |  |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |  | 5
Amortization of net actuarial loss (gain) |  |  |  | 3 |  |  |  | 3 |  |  |  | 4 |  |  |  |  | 4
Unrealized gain (loss) on investments, net of tax |  |  |  |  | 1 |  |  | 1 |  |  |  |  | $ (2) |  |  |  | (2)
Reclassification adjustments included in net income, net of tax |  |  |  |  | (3) |  |  | 3 |  |  |  |  |  |  |  |  |
Reclassification adjustments included in net income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 452 |  | 452
Net income |  |  |  |  |  | 534 |  | 534 |  |  |  |  |  |  |  |  | 454
Dividends declared on common stock |  |  |  |  |  | (406) |  |  |  |  |  |  |  |  | (271) |  |
Preferred stock dividends and distributions declared |  |  |  |  |  | (2) |  |  |  |  |  |  |  |  |  |  |
Income Attributable to Noncontrolling Interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 | 2
Distributions, redemptions, and other changes in noncontrolling interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (9) |
Preferred stock redeemed |  |  |  |  |  |  | (7) |  |  |  |  |  |  |  |  |  |
End of period, shares at Dec. 31, 2013 |  |  |  |  |  |  |  |  | 266,137 |  |  |  |  |  |  |  |
Total Equity, end at Dec. 31, 2013 | 841 | $ 3,257 | (2) | (17) | 15 | 724 | $ 37 | 4,857 | $ 3 | $ 4,715 | (22) | (21) |  | $ (1) | (1,242) | 37 | 3,491
Common stock issued |  |  |  |  |  |  |  |  |  | 59 |  |  |  |  |  |  |
Number of Shares Issued |  |  |  |  |  |  |  |  | 9,371 |  |  |  |  |  |  |  |
Common stock repurchased |  |  |  |  |  |  |  |  |  | $ (7) |  |  |  |  |  |  |
Common stock repurchased, shares |  |  |  |  |  |  |  |  | (271) |  |  |  |  |  |  |  |
Common stock reissued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reissued, shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion option on convertible debt |  |  |  |  |  |  |  |  |  | $ 7 |  |  |  |  |  |  |
Common stock reacquired, value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reacquired, shares |  |  |  |  |  |  |  |  | (53) |  |  |  |  |  |  |  |
Stockholder contribution |  | 495 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return of stockholder contribution |  | (178) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain arising during the period |  |  |  | (11) |  |  |  | (11) |  |  |  | $ (29) |  |  |  |  | (29)
Prior service credit adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization of net actuarial loss (gain) |  |  |  | 2 |  |  |  | 2 |  |  |  | $ 3 |  |  |  |  | 3
Amortization of prior service credit |  |  |  |  |  |  |  |  |  |  |  | (1) |  |  |  |  | (1)
Unrealized gain (loss) on investments, net of tax |  |  |  |  | $ 4 |  |  | 4 |  |  |  |  | $ (1) |  |  |  | (1)
Reclassification adjustments included in net income, net of tax |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reclassification adjustments included in net income |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1 |  |  | (1)
Net income (loss) attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 477 |  | 477
Net income |  |  |  |  |  | 567 |  | $ 567 |  |  |  |  |  |  |  |  | 479
Dividends declared on common stock |  |  |  |  |  | (457) |  |  |  |  |  |  |  |  | (293) |  |
Preferred stock dividends and distributions declared |  |  |  |  |  | (2) |  |  |  |  |  |  |  |  |  |  |
Income Attributable to Noncontrolling Interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 | $ 2
Distributions, redemptions, and other changes in noncontrolling interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2) |
Preferred stock redeemed |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
End of period, shares at Dec. 31, 2014 |  |  |  |  |  |  |  | 84,100 | 275,184 |  |  |  |  |  |  |  | 275,200
Total Equity, end at Dec. 31, 2014 | 841 | 3,574 | (7) | (26) | $ 19 | 832 | $ 37 | $ 5,277 | $ 3 | $ 4,774 | (49) | (48) | (1) |  | (1,058) | 37 | $ 3,707
Common stock issued |  |  |  |  |  |  |  |  |  | 65 |  |  |  |  |  |  |
Number of Shares Issued |  |  |  |  |  |  |  |  | 2,062 |  |  |  |  |  |  |  |
Common stock repurchased |  |  |  |  |  |  |  |  |  | (12) |  |  |  |  |  |  |
Common stock repurchased, shares |  |  |  |  |  |  |  |  | (306) |  |  |  |  |  |  |  |
Common stock reissued |  |  |  |  |  |  |  |  |  | $ 10 |  |  |  |  |  |  |
Common stock reissued, shares |  |  |  |  |  |  |  |  | 288 |  |  |  |  |  |  |  |
Conversion option on convertible debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reacquired, value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reacquired, shares |  |  |  |  |  |  |  |  | (65) |  |  |  |  |  |  |  |
Stockholder contribution |  | $ 150 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return of stockholder contribution |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain arising during the period |  |  |  | 3 |  |  |  | 3 |  |  |  | $ 1 |  |  |  |  | 1
Prior service credit adjustment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization of net actuarial loss (gain) |  |  |  | 4 |  |  |  | 4 |  |  |  | $ 5 |  |  |  |  | 5
Amortization of prior service credit |  |  |  |  |  |  |  |  |  |  |  | (1) |  |  |  |  | (1)
Unrealized gain (loss) on investments, net of tax |  |  |  |  | (1) |  |  | (1) |  |  |  |  | (3) |  |  |  | (3)
Reclassification adjustments included in net income, net of tax |  |  |  |  | (5) |  |  | 5 |  |  |  |  |  |  |  |  |
Reclassification adjustments included in net income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income (loss) attributable to CMS Energy |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 523 |  | 523
Net income |  |  |  |  |  | 594 |  | $ 594 |  |  |  |  |  |  |  |  | 525
Dividends declared on common stock |  |  |  |  |  | (474) |  |  |  |  |  |  |  |  | (320) |  |
Preferred stock dividends and distributions declared |  |  |  |  |  | (2) |  |  |  |  |  |  |  |  |  |  |
Income Attributable to Noncontrolling Interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 | $ 2
Distributions, redemptions, and other changes in noncontrolling interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2) |
Preferred stock redeemed |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
End of period, shares at Dec. 31, 2015 |  |  |  |  |  |  |  | 84,100 | 277,163 |  |  |  |  |  |  |  | 277,200
Total Equity, end at Dec. 31, 2015 | $ 841 | $ 3,724 | $ (6) | $ (19) | $ 13 | $ 950 | $ 37 | $ 5,546 | $ 3 | $ 4,837 | $ (47) | $ (43) | $ (4) |  | $ (855) | $ 37 | $ 3,975

X
- Definition Adjustments to Additional Paid in Capital, Return of stockholder contribution + References No definition available. + Details
Name: | cms_AdjustmentsToAdditionalPaidInCapitalReturnOfStockholderContribution
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments to Additional Paid in Capital Stockholder Contribution + References No definition available. + Details
Name: | cms_AdjustmentsToAdditionalPaidInCapitalStockholderContribution
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Common stock reissued shares + References No definition available. + Details
Name: | cms_CommonStockReissuedShares
Namespace Prefix: | cms_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the value of shares reissued during the period. Upon reissuance, the common stock reissued is outstanding. + References No definition available. + Details
Name: | cms_CommonStockReissuedValue
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Changes in noncontrolling interest balance from payment of dividends or other distributions or transactions affecting noncontrolling interest holders. + References No definition available. + Details
Name: | cms_OtherChangesInNoncontrollingInterests
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_DividendsCommonStockCash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_DividendsPreferredStockCash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=51831255 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.18) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.22) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=51831270 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591551-111686 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 + Details
Name: | us-gaap_NetIncomeLossAttributableToNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Prior Service Cost -URI http://asc.fasb.org/extlink&oid=49177896 + Details
Name: | us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
Name: | us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph c -URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41638-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4569616-111683 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591552-111686 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591551-111686 + Details
Name: | us-gaap_ProfitLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of new stock issued during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares related to Restricted Stock Award forfeited during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The net amount of stock issued during the period upon the conversion of convertible securities, net of adjustments (for example, to additional paid in capital) including the write-off of an equity component recognized to record the convertible debt instrument as two separate components - a debt component and an equity component. This item is meant to disclose the value of shares issued on conversion of convertible securities that were recorded as two separate (debt and equity) components. + References No definition available. + Details
Name: | us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecuritiesNetOfAdjustments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
Name: | us-gaap_StockIssuedDuringPeriodValueNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Value of stock related to Restricted Stock Awards forfeited during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
Name: | us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Equity impact of the value of stock bought back by the entity at the exercise price or redemption price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
Name: | us-gaap_StockRedeemedOrCalledDuringPeriodValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
Name: | us-gaap_StockRepurchasedDuringPeriodShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
Name: | us-gaap_StockRepurchasedDuringPeriodValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4I -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4590271-111686 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568740-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568447-111683 + Details
Name: | us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=cms_ConsumersEnergyCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AdditionalPaidInCapitalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_PreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_NoncontrollingInterestMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |