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Income Taxes (Tables) | 12 Months Ended
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Dec. 31, 2018
Income Taxes [Line Items] |
Schedule Of Effective Income Tax Rate Reconciliation | Presented in the following table is the difference between actual income tax expense on continuing operations and income tax expense computed by applying the statutory U.S. federal income tax rate:
In Millions, Except Tax Rate |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Income from continuing operations before income taxes |  | $ | 774 |  |  | $ | 886 |  |  | $ | 826 |
Income tax expense at statutory rate |  | 163 |  |  | 310 |  |  | 289 |
Increase (decrease) in income taxes from: |  |  |  |  |  |
State and local income taxes, net of federal effect 1 |  | 46 |  |  | 26 |  |  | 37 |
Accelerated flow-through of regulatory tax benefits 2 |  | (39 | ) |  | (39 | ) |  | (39 | )
TCJA excess deferred taxes 3 |  | (26 | ) |  | — |  |  | — |
Production tax credits |  | (14 | ) |  | (8 | ) |  | (9 | )
Research and development tax credits, net 4 |  | (11 | ) |  | (1 | ) |  | (2 | )
Impact of the TCJA 5 |  | (4 | ) |  | 148 |  |  | — |
Other, net |  | — |  |  | (12 | ) |  | (3 | )
Income tax expense |  | $ | 115 |  |  | $ | 424 |  |  | $ | 273 |
Effective tax rate |  | 14.9 | % |  | 47.9 | % |  | 33.1 | %
Consumers |  |  |  |  |  |
Income from continuing operations before income taxes |  | $ | 847 |  |  | $ | 971 |  |  | $ | 936 |
Income tax expense at statutory rate |  | 178 |  |  | 340 |  |  | 328 |
Increase (decrease) in income taxes from: |  |  |  |  |  |
State and local income taxes, net of federal effect 1 |  | 51 |  |  | 30 |  |  | 44 |
Accelerated flow-through of regulatory tax benefits 2 |  | (39 | ) |  | (39 | ) |  | (39 | )
TCJA excess deferred taxes 3 |  | (26 | ) |  | — |  |  | — |
Production tax credits |  | (12 | ) |  | (8 | ) |  | (9 | )
Research and development tax credits, net 4 |  | (11 | ) |  | (1 | ) |  | (2 | )
Impact of the TCJA 5 |  | 1 |  |  | 33 |  |  | — |
Other, net |  | — |  |  | (16 | ) |  | (2 | )
Income tax expense |  | $ | 142 |  |  | $ | 339 |  |  | $ | 320 |
Effective tax rate |  | 16.8 | % |  | 34.9 | % |  | 34.2 | %
1 | In September 2017, CMS Energy completed the evaluation of its methodology for the state apportionment of Consumers’ electricity sales to MISO, taking into account recent state tax law developments in the electric utility sector. To recognize the anticipated refund and the impact of the expected lower effective tax rate on their deferred state tax liabilities, CMS Energy, including Consumers, recorded a $14 million income tax benefit in 2017. These tax benefits were net of reserves for uncertain tax positions and primarily attributable to Consumers. In April 2018, CMS Energy amended its 2013 Michigan Corporate Income Tax return and submitted a refund claim for taxes previously paid. In November 2018, the refund claim was denied by the State of Michigan. CMS Energy has submitted a petition for informal conference.
2 | In 2013, the MPSC issued an order authorizing Consumers to accelerate the flow-through to electric and gas customers of certain income tax benefits associated primarily with the cost of removal of plant placed in service before 1993. Consumers implemented this regulatory treatment beginning in 2014. This change, which also accelerates Consumers’ recognition of the income tax benefits, reduced Consumers’ income tax expense by $39 million for each of the years ended December 31, 2018, 2017, and 2016.
3 | In December 2017, Consumers remeasured its deferred tax assets and liabilities at the new federal tax rate enacted by the TCJA and recorded a $1.8 billion regulatory liability. This regulatory liability relates to the excess deferred taxes arising from accelerated tax depreciation on assets in rate base that are governed by normalization provisions of the Internal Revenue Code. The normalization provisions require that the excess deferred taxes be refunded to customers over the remaining average service life of the associated assets. In January 2018, Consumers began to reduce this regulatory liability by crediting income tax expense. Consumers has fully reserved for the eventual refund of these excess deferred taxes that it has credited to income tax expense in a separate regulatory liability established by reducing revenue, and will continue to do so until these benefits are passed on to customers in accordance with an MPSC order, expected to be issued in 2019. At December 31, 2018, this reserve for refund of these excess deferred taxes totaled $35 million.
4 | In March 2018, Consumers finalized a study of research and development tax credits for the tax years 2012 through 2016. As a result, Consumers recognized an $8 million increase in the credit, net of reserves for uncertain tax positions.
5 | In December 2017, CMS Energy and Consumers recorded a reasonable estimate to measure and account for the impact of the TCJA. The 2018 amount includes the true-up of their estimate and elimination of $9 million valuation allowance on the sequestration of alternative minimum tax credits.
Significant Components Of Income Tax Expense | Presented in the following table are the significant components of income tax expense on continuing operations:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Current income taxes |  |  |  |  |  |
Federal |  | $ | (67 | ) |  | $ | — |  |  | $ | — |
State and local |  | — |  |  | 6 |  |  | 9 |
|  | $ | (67 | ) |  | $ | 6 |  |  | $ | 9 |
Deferred income taxes |  |  |  |  |  |
Federal |  | $ | 112 |  |  | $ | 368 |  |  | $ | 200 |
State and local |  | 58 |  |  | 36 |  |  | 47 |
|  | $ | 170 |  |  | $ | 404 |  |  | $ | 247 |
Deferred income tax credit |  | 12 |  |  | 14 |  |  | 17 |
Tax expense |  | $ | 115 |  |  | $ | 424 |  |  | $ | 273 |
Consumers |  |  |  |  |  |
Current income taxes |  |  |  |  |  |
Federal |  | $ | 6 |  |  | $ | 159 |  |  | $ | 9 |
State and local |  | 13 |  |  | 17 |  |  | 22 |
|  | $ | 19 |  |  | $ | 176 |  |  | $ | 31 |
Deferred income taxes |  |  |  |  |  |
Federal |  | $ | 60 |  |  | $ | 120 |  |  | $ | 227 |
State and local |  | 51 |  |  | 29 |  |  | 45 |
|  | $ | 111 |  |  | $ | 149 |  |  | $ | 272 |
Deferred income tax credit |  | 12 |  |  | 14 |  |  | 17 |
Tax expense |  | $ | 142 |  |  | $ | 339 |  |  | $ | 320 |
Principal Components Of Deferred Income Tax Assets And Liailities | Presented in the following table are the principal components of deferred income tax assets (liabilities) recognized:
In Millions |
December 31 | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |
Deferred income tax assets |  |  |  |
Tax loss and credit carryforwards |  | $ | 385 |  |  | $ | 453 |
Net regulatory tax liability |  | 395 |  |  | 411 |
Reserves and accruals |  | 39 |  |  | 40 |
Total deferred income tax assets |  | $ | 819 |  |  | $ | 904 |
Valuation allowance |  | (8 | ) |  | (15 | )
Total deferred income tax assets, net of valuation allowance |  | $ | 811 |  |  | $ | 889 |
Deferred income tax liabilities |  |  |  |
Plant, property, and equipment |  | $ | (1,955 | ) |  | $ | (1,891 | )
Employee benefits |  | (165 | ) |  | (96 | )
Securitized costs |  | (65 | ) |  | (71 | )
Gas inventory |  | (35 | ) |  | (37 | )
Other |  | (78 | ) |  | (63 | )
Total deferred income tax liabilities |  | $ | (2,298 | ) |  | $ | (2,158 | )
Total net deferred income tax liabilities |  | $ | (1,487 | ) |  | $ | (1,269 | )
Consumers |  |  |  |
Deferred income tax assets |  |  |  |
Net regulatory tax liability |  | $ | 395 |  |  | $ | 411 |
Tax loss and credit carryforwards |  | 64 |  |  | 101 |
Reserves and accruals |  | 21 |  |  | 21 |
Total deferred income tax assets |  | $ | 480 |  |  | $ | 533 |
Deferred income tax liabilities |  |  |  |
Plant, property, and equipment |  | $ | (1,943 | ) |  | $ | (1,901 | )
Employee benefits |  | (172 | ) |  | (105 | )
Securitized costs |  | (65 | ) |  | (71 | )
Gas inventory |  | (35 | ) |  | (37 | )
Other |  | (74 | ) |  | (59 | )
Total deferred income tax liabilities |  | $ | (2,289 | ) |  | $ | (2,173 | )
Total net deferred income tax liabilities |  | $ | (1,809 | ) |  | $ | (1,640 | )
Loss And Credit Carryforwards | Presented in the following table are the tax loss and credit carryforwards at December 31, 2018:
In Millions
| Gross Amount |  | Tax Attribute |  | Expiration
CMS Energy, including Consumers |  |  |  |  |
Federal net operating loss carryforward |  | $ | 603 |  |  | $ | 126 |  | 2034 – 2036
Local net operating loss carryforwards |  | 406 |  |  | 4 |  | 2023 – 2036
General business credits |  | 184 |  |  | 184 |  | 2018 – 2038
Alternative minimum tax credits |  | 68 |  |  | 68 |  | Not applicable
Federal capital loss carryover |  | 12 |  |  | 2 |  | 2023
State capital loss carryover |  | 10 |  |  | 1 |  | 2023
Total tax attributes |  |  |  | $ | 385 |  |
Consumers |  |  |  |  |
Federal net operating loss carryforward |  | $ | 222 |  |  | $ | 47 |  | 2034 – 2036
General business credits |  | 17 |  |  | 17 |  | 2032 – 2038
Total tax attributes |  |  |  | $ | 64 |  |
Reconciliation Of Beginning And Ending Uncertain Tax Benefits | Presented in the following table is a reconciliation of the beginning and ending amount of uncertain tax benefits:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Balance at beginning of period |  | $ | 14 |  |  | $ | 5 |  |  | $ | 6 |
Additions for current-year tax positions |  | 1 |  |  | 10 |  |  | — |
Additions for prior-year tax positions |  | 4 |  |  | — |  |  | — |
Reductions for prior-year tax positions |  | — |  |  | (1 | ) |  | — |
Settlements |  | — |  |  | — |  |  | (1 | )
Balance at end of period |  | $ | 19 |  |  | $ | 14 |  |  | $ | 5 |
Consumers |  |  |  |  |  |  |  |  |
Balance at beginning of period |  | $ | 21 |  |  | $ | 5 |  |  | $ | 6 |
Additions for current-year tax positions |  | 2 |  |  | 17 |  |  | — |
Additions for prior-year tax positions |  | 5 |  |  | — |  |  | — |
Reductions for prior-year tax positions |  | — |  |  | (1 | ) |  | — |
Settlements |  | — |  |  | — |  |  | (1 | )
Balance at end of period |  | $ | 28 |  |  | $ | 21 |  |  | $ | 5 |
Consumers Energy Company |
Income Taxes [Line Items] |
Schedule Of Effective Income Tax Rate Reconciliation | Presented in the following table is the difference between actual income tax expense on continuing operations and income tax expense computed by applying the statutory U.S. federal income tax rate:
In Millions, Except Tax Rate |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Income from continuing operations before income taxes |  | $ | 774 |  |  | $ | 886 |  |  | $ | 826 |
Income tax expense at statutory rate |  | 163 |  |  | 310 |  |  | 289 |
Increase (decrease) in income taxes from: |  |  |  |  |  |
State and local income taxes, net of federal effect 1 |  | 46 |  |  | 26 |  |  | 37 |
Accelerated flow-through of regulatory tax benefits 2 |  | (39 | ) |  | (39 | ) |  | (39 | )
TCJA excess deferred taxes 3 |  | (26 | ) |  | — |  |  | — |
Production tax credits |  | (14 | ) |  | (8 | ) |  | (9 | )
Research and development tax credits, net 4 |  | (11 | ) |  | (1 | ) |  | (2 | )
Impact of the TCJA 5 |  | (4 | ) |  | 148 |  |  | — |
Other, net |  | — |  |  | (12 | ) |  | (3 | )
Income tax expense |  | $ | 115 |  |  | $ | 424 |  |  | $ | 273 |
Effective tax rate |  | 14.9 | % |  | 47.9 | % |  | 33.1 | %
Consumers |  |  |  |  |  |
Income from continuing operations before income taxes |  | $ | 847 |  |  | $ | 971 |  |  | $ | 936 |
Income tax expense at statutory rate |  | 178 |  |  | 340 |  |  | 328 |
Increase (decrease) in income taxes from: |  |  |  |  |  |
State and local income taxes, net of federal effect 1 |  | 51 |  |  | 30 |  |  | 44 |
Accelerated flow-through of regulatory tax benefits 2 |  | (39 | ) |  | (39 | ) |  | (39 | )
TCJA excess deferred taxes 3 |  | (26 | ) |  | — |  |  | — |
Production tax credits |  | (12 | ) |  | (8 | ) |  | (9 | )
Research and development tax credits, net 4 |  | (11 | ) |  | (1 | ) |  | (2 | )
Impact of the TCJA 5 |  | 1 |  |  | 33 |  |  | — |
Other, net |  | — |  |  | (16 | ) |  | (2 | )
Income tax expense |  | $ | 142 |  |  | $ | 339 |  |  | $ | 320 |
Effective tax rate |  | 16.8 | % |  | 34.9 | % |  | 34.2 | %
1 | In September 2017, CMS Energy completed the evaluation of its methodology for the state apportionment of Consumers’ electricity sales to MISO, taking into account recent state tax law developments in the electric utility sector. To recognize the anticipated refund and the impact of the expected lower effective tax rate on their deferred state tax liabilities, CMS Energy, including Consumers, recorded a $14 million income tax benefit in 2017. These tax benefits were net of reserves for uncertain tax positions and primarily attributable to Consumers. In April 2018, CMS Energy amended its 2013 Michigan Corporate Income Tax return and submitted a refund claim for taxes previously paid. In November 2018, the refund claim was denied by the State of Michigan. CMS Energy has submitted a petition for informal conference.
2 | In 2013, the MPSC issued an order authorizing Consumers to accelerate the flow-through to electric and gas customers of certain income tax benefits associated primarily with the cost of removal of plant placed in service before 1993. Consumers implemented this regulatory treatment beginning in 2014. This change, which also accelerates Consumers’ recognition of the income tax benefits, reduced Consumers’ income tax expense by $39 million for each of the years ended December 31, 2018, 2017, and 2016.
3 | In December 2017, Consumers remeasured its deferred tax assets and liabilities at the new federal tax rate enacted by the TCJA and recorded a $1.8 billion regulatory liability. This regulatory liability relates to the excess deferred taxes arising from accelerated tax depreciation on assets in rate base that are governed by normalization provisions of the Internal Revenue Code. The normalization provisions require that the excess deferred taxes be refunded to customers over the remaining average service life of the associated assets. In January 2018, Consumers began to reduce this regulatory liability by crediting income tax expense. Consumers has fully reserved for the eventual refund of these excess deferred taxes that it has credited to income tax expense in a separate regulatory liability established by reducing revenue, and will continue to do so until these benefits are passed on to customers in accordance with an MPSC order, expected to be issued in 2019. At December 31, 2018, this reserve for refund of these excess deferred taxes totaled $35 million.
4 | In March 2018, Consumers finalized a study of research and development tax credits for the tax years 2012 through 2016. As a result, Consumers recognized an $8 million increase in the credit, net of reserves for uncertain tax positions.
5 | In December 2017, CMS Energy and Consumers recorded a reasonable estimate to measure and account for the impact of the TCJA. The 2018 amount includes the true-up of their estimate and elimination of $9 million valuation allowance on the sequestration of alternative minimum tax credits.
Significant Components Of Income Tax Expense | Presented in the following table are the significant components of income tax expense on continuing operations:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Current income taxes |  |  |  |  |  |
Federal |  | $ | (67 | ) |  | $ | — |  |  | $ | — |
State and local |  | — |  |  | 6 |  |  | 9 |
|  | $ | (67 | ) |  | $ | 6 |  |  | $ | 9 |
Deferred income taxes |  |  |  |  |  |
Federal |  | $ | 112 |  |  | $ | 368 |  |  | $ | 200 |
State and local |  | 58 |  |  | 36 |  |  | 47 |
|  | $ | 170 |  |  | $ | 404 |  |  | $ | 247 |
Deferred income tax credit |  | 12 |  |  | 14 |  |  | 17 |
Tax expense |  | $ | 115 |  |  | $ | 424 |  |  | $ | 273 |
Consumers |  |  |  |  |  |
Current income taxes |  |  |  |  |  |
Federal |  | $ | 6 |  |  | $ | 159 |  |  | $ | 9 |
State and local |  | 13 |  |  | 17 |  |  | 22 |
|  | $ | 19 |  |  | $ | 176 |  |  | $ | 31 |
Deferred income taxes |  |  |  |  |  |
Federal |  | $ | 60 |  |  | $ | 120 |  |  | $ | 227 |
State and local |  | 51 |  |  | 29 |  |  | 45 |
|  | $ | 111 |  |  | $ | 149 |  |  | $ | 272 |
Deferred income tax credit |  | 12 |  |  | 14 |  |  | 17 |
Tax expense |  | $ | 142 |  |  | $ | 339 |  |  | $ | 320 |
Principal Components Of Deferred Income Tax Assets And Liailities | Presented in the following table are the principal components of deferred income tax assets (liabilities) recognized:
In Millions |
December 31 | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |
Deferred income tax assets |  |  |  |
Tax loss and credit carryforwards |  | $ | 385 |  |  | $ | 453 |
Net regulatory tax liability |  | 395 |  |  | 411 |
Reserves and accruals |  | 39 |  |  | 40 |
Total deferred income tax assets |  | $ | 819 |  |  | $ | 904 |
Valuation allowance |  | (8 | ) |  | (15 | )
Total deferred income tax assets, net of valuation allowance |  | $ | 811 |  |  | $ | 889 |
Deferred income tax liabilities |  |  |  |
Plant, property, and equipment |  | $ | (1,955 | ) |  | $ | (1,891 | )
Employee benefits |  | (165 | ) |  | (96 | )
Securitized costs |  | (65 | ) |  | (71 | )
Gas inventory |  | (35 | ) |  | (37 | )
Other |  | (78 | ) |  | (63 | )
Total deferred income tax liabilities |  | $ | (2,298 | ) |  | $ | (2,158 | )
Total net deferred income tax liabilities |  | $ | (1,487 | ) |  | $ | (1,269 | )
Consumers |  |  |  |
Deferred income tax assets |  |  |  |
Net regulatory tax liability |  | $ | 395 |  |  | $ | 411 |
Tax loss and credit carryforwards |  | 64 |  |  | 101 |
Reserves and accruals |  | 21 |  |  | 21 |
Total deferred income tax assets |  | $ | 480 |  |  | $ | 533 |
Deferred income tax liabilities |  |  |  |
Plant, property, and equipment |  | $ | (1,943 | ) |  | $ | (1,901 | )
Employee benefits |  | (172 | ) |  | (105 | )
Securitized costs |  | (65 | ) |  | (71 | )
Gas inventory |  | (35 | ) |  | (37 | )
Other |  | (74 | ) |  | (59 | )
Total deferred income tax liabilities |  | $ | (2,289 | ) |  | $ | (2,173 | )
Total net deferred income tax liabilities |  | $ | (1,809 | ) |  | $ | (1,640 | )
Loss And Credit Carryforwards | Presented in the following table are the tax loss and credit carryforwards at December 31, 2018:
In Millions
| Gross Amount |  | Tax Attribute |  | Expiration
CMS Energy, including Consumers |  |  |  |  |
Federal net operating loss carryforward |  | $ | 603 |  |  | $ | 126 |  | 2034 – 2036
Local net operating loss carryforwards |  | 406 |  |  | 4 |  | 2023 – 2036
General business credits |  | 184 |  |  | 184 |  | 2018 – 2038
Alternative minimum tax credits |  | 68 |  |  | 68 |  | Not applicable
Federal capital loss carryover |  | 12 |  |  | 2 |  | 2023
State capital loss carryover |  | 10 |  |  | 1 |  | 2023
Total tax attributes |  |  |  | $ | 385 |  |
Consumers |  |  |  |  |
Federal net operating loss carryforward |  | $ | 222 |  |  | $ | 47 |  | 2034 – 2036
General business credits |  | 17 |  |  | 17 |  | 2032 – 2038
Total tax attributes |  |  |  | $ | 64 |  |
Reconciliation Of Beginning And Ending Uncertain Tax Benefits | Presented in the following table is a reconciliation of the beginning and ending amount of uncertain tax benefits:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Balance at beginning of period |  | $ | 14 |  |  | $ | 5 |  |  | $ | 6 |
Additions for current-year tax positions |  | 1 |  |  | 10 |  |  | — |
Additions for prior-year tax positions |  | 4 |  |  | — |  |  | — |
Reductions for prior-year tax positions |  | — |  |  | (1 | ) |  | — |
Settlements |  | — |  |  | — |  |  | (1 | )
Balance at end of period |  | $ | 19 |  |  | $ | 14 |  |  | $ | 5 |
Consumers |  |  |  |  |  |  |  |  |
Balance at beginning of period |  | $ | 21 |  |  | $ | 5 |  |  | $ | 6 |
Additions for current-year tax positions |  | 2 |  |  | 17 |  |  | — |
Additions for prior-year tax positions |  | 5 |  |  | — |  |  | — |
Reductions for prior-year tax positions |  | — |  |  | (1 | ) |  | — |
Settlements |  | — |  |  | — |  |  | (1 | )
Balance at end of period |  | $ | 28 |  |  | $ | 21 |  |  | $ | 5 |

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- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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Name: | dei_LegalEntityAxis=cms_ConsumersEnergyCompanyMember
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Data Type: | na
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