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Income Taxes | 3 Months Ended
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Mar. 31, 2019
Income Taxes [Line Items] |
Income Taxes | Income Taxes Presented in the following table is a reconciliation of the statutory U.S. federal income tax rate to the effective income tax rate from continuing operations:
Three Months Ended March 31 |  | 2019 |  |  | 2018 |
CMS Energy, including Consumers |  |  |  |
U.S. federal income tax rate |  | 21.0 | % |  | 21.0 | %
Increase (decrease) in income taxes from: |  |  |  |
State and local income taxes, net of federal effect |  | 5.4 |  |  | 5.7 |
TCJA excess deferred taxes 1 |  | (3.5 | ) |  | (2.9 | )
Production tax credits |  | (2.4 | ) |  | (1.5 | )
Accelerated flow-through of regulatory tax benefits 2 |  | (1.5 | ) |  | (5.0 | )
Research and development tax credits, net 3 |  | (0.2 | ) |  | (2.8 | )
Other, net |  | (0.4 | ) |  | (0.3 | )
Effective tax rate |  | 18.4 | % |  | 14.2 | %
Consumers |  |  |  |
U.S. federal income tax rate |  | 21.0 | % |  | 21.0 | %
Increase (decrease) in income taxes from: |  |  |  |
State and local income taxes, net of federal effect |  | 5.6 |  |  | 6.2 |
TCJA excess deferred taxes 1 |  | (3.3 | ) |  | (2.9 | )
Accelerated flow-through of regulatory tax benefits 2 |  | (2.5 | ) |  | (4.8 | )
Production tax credits |  | (1.0 | ) |  | (1.1 | )
Research and development tax credits, net 3 |  | (0.2 | ) |  | (2.7 | )
Other, net |  | (0.3 | ) |  | (0.3 | )
Effective tax rate |  | 19.3 | % |  | 15.4 | %
1 | 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 non‑current 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 March 31, 2019, this reserve for refund of these excess deferred taxes totaled $48 million.
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, with the electric portion ending in 2018. This change, which also accelerates Consumers’ recognition of the income tax benefits, reduced Consumers’ income tax expense by $7 million for the three months ended March 31, 2019 and by $14 million for the three months ended March 31, 2018.
3 | 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, at that time.
Consumers Energy Company |
Income Taxes [Line Items] |
Income Taxes | Income Taxes Presented in the following table is a reconciliation of the statutory U.S. federal income tax rate to the effective income tax rate from continuing operations:
Three Months Ended March 31 |  | 2019 |  |  | 2018 |
CMS Energy, including Consumers |  |  |  |
U.S. federal income tax rate |  | 21.0 | % |  | 21.0 | %
Increase (decrease) in income taxes from: |  |  |  |
State and local income taxes, net of federal effect |  | 5.4 |  |  | 5.7 |
TCJA excess deferred taxes 1 |  | (3.5 | ) |  | (2.9 | )
Production tax credits |  | (2.4 | ) |  | (1.5 | )
Accelerated flow-through of regulatory tax benefits 2 |  | (1.5 | ) |  | (5.0 | )
Research and development tax credits, net 3 |  | (0.2 | ) |  | (2.8 | )
Other, net |  | (0.4 | ) |  | (0.3 | )
Effective tax rate |  | 18.4 | % |  | 14.2 | %
Consumers |  |  |  |
U.S. federal income tax rate |  | 21.0 | % |  | 21.0 | %
Increase (decrease) in income taxes from: |  |  |  |
State and local income taxes, net of federal effect |  | 5.6 |  |  | 6.2 |
TCJA excess deferred taxes 1 |  | (3.3 | ) |  | (2.9 | )
Accelerated flow-through of regulatory tax benefits 2 |  | (2.5 | ) |  | (4.8 | )
Production tax credits |  | (1.0 | ) |  | (1.1 | )
Research and development tax credits, net 3 |  | (0.2 | ) |  | (2.7 | )
Other, net |  | (0.3 | ) |  | (0.3 | )
Effective tax rate |  | 19.3 | % |  | 15.4 | %
1 | 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 non‑current 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 March 31, 2019, this reserve for refund of these excess deferred taxes totaled $48 million.
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, with the electric portion ending in 2018. This change, which also accelerates Consumers’ recognition of the income tax benefits, reduced Consumers’ income tax expense by $7 million for the three months ended March 31, 2019 and by $14 million for the three months ended March 31, 2018.
3 | 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, at that time.

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- Definition Income Taxes [Line Items] + References No definition available. + Details
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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -URI http://asc.fasb.org/topic&trid=2144680 + Details
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