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Significant Accounting Policies (Policy) | 12 Months Ended
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Dec. 31, 2018
Significant Accounting Policies [Line Items] |
Principles of Consolidation | Principles of Consolidation: CMS Energy and Consumers prepare their consolidated financial statements in conformity with GAAP. CMS Energy’s consolidated financial statements comprise CMS Energy, Consumers, CMS Enterprises, and all other entities in which CMS Energy has a controlling financial interest or is the primary beneficiary. Consumers’ consolidated financial statements comprise Consumers and all other entities in which it has a controlling financial interest or is the primary beneficiary. CMS Energy uses the equity method of accounting for investments in companies and partnerships that are not consolidated, where they have significant influence over operations and financial policies but are not the primary beneficiary. CMS Energy and Consumers eliminate intercompany transactions and balances.
Use of Estimates | Use of Estimates: CMS Energy and Consumers are required to make estimates using assumptions that may affect reported amounts and disclosures. Actual results could differ from those estimates.
Contingencies | Contingencies: CMS Energy and Consumers record estimated liabilities for contingencies on their consolidated financial statements when it is probable that a liability has been incurred and when the amount of loss can be reasonably estimated. For environmental remediation projects in which the timing of estimated expenditures is considered reliably determinable, CMS Energy and Consumers record the liability at its net present value, using a discount rate equal to the interest rate on monetary assets that are essentially risk-free and have maturities comparable to that of the environmental liability. CMS Energy and Consumers expense legal fees as incurred; fees incurred but not yet billed are accrued based on estimates of work performed.
Debt Issuance Costs, Discounts, Premiums, and Refinancing Costs | Debt Issuance Costs, Discounts, Premiums, and Refinancing Costs: Upon the issuance of long-term debt, CMS Energy and Consumers defer issuance costs, discounts, and premiums and amortize those amounts over the terms of the associated debt. Debt issuance costs are presented as a direct deduction from the carrying amount of long-term debt on the balance sheet. Upon the refinancing of long-term debt, Consumers, as a regulated entity, defers any remaining unamortized issuance costs, discounts, and premiums associated with the refinanced debt and amortizes those amounts over the term of the newly issued debt. For the non‑regulated portions of CMS Energy’s business, any remaining unamortized issuance costs, discounts, and premiums associated with extinguished debt are charged to earnings.
Derivative Instruments | Derivative Instruments: In order to support ongoing operations, CMS Energy and Consumers enter into contracts for the future purchase and sale of various commodities, such as electricity, natural gas, and coal. These forward contracts are generally long-term in nature and result in physical delivery of the commodity at a contracted price. Most of these contracts are not subject to derivative accounting for one or more of the following reasons:
• | they do not have a notional amount (that is, a number of units specified in a derivative instrument, such as MWh of electricity or bcf of natural gas)
• | they qualify for the normal purchases and sales exception
• | there is not an active market for the commodity
Consumers also uses FTRs to manage price risk related to electricity transmission congestion. An FTR is a financial instrument that entitles its holder to receive compensation or requires its holder to remit payment for congestion-related transmission charges. Consumers accounts for FTRs as derivatives. Additionally, CMS Energy uses interest rate swaps to manage its interest rate risk on certain long-term debt transactions. CMS Energy and Consumers record derivative contracts that do not qualify for the normal purchases and sales exception at fair value on their consolidated balance sheets. Each reporting period, the resulting asset or liability is adjusted to reflect any change in the fair value of the contract. At Consumers, changes in fair value are deferred as regulatory assets or liabilities. At CMS Energy, the changes are reported in earnings or, if the derivative qualifies for cash flow hedge accounting, in AOCI. For details regarding CMS Energy’s and Consumers’ derivative instruments recorded at fair value, see Note 6, Fair Value Measurements.
Earnings Per Share | : CMS Energy calculates basic and diluted EPS using the weighted-average number of shares of common stock and dilutive potential common stock outstanding during the period. Potential common stock, for purposes of determining diluted EPS, includes the effects of nonvested stock awards and forward equity sales. CMS Energy computes the effect on potential common stock using the treasury stock method. Diluted EPS excludes the impact of antidilutive securities, which are those securities resulting in an increase in EPS or a decrease in loss per share. For EPS computations, see Note 15, Earnings Per Share—CMS Energy.
Impairment of Long-Lived Assets | Impairment of Long-Lived Assets and Equity Method Investments: CMS Energy and Consumers perform tests of impairment if certain triggering events occur or if there has been a decline in value that may be other than temporary. CMS Energy and Consumers evaluate long-lived assets held in use for impairment by calculating the undiscounted future cash flows expected to result from the use of the asset and its eventual disposition. If the undiscounted future cash flows are less than the carrying amount, CMS Energy and Consumers recognize an impairment loss equal to the amount by which the carrying amount exceeds the fair value. CMS Energy and Consumers estimate the fair value of the asset using quoted market prices, market prices of similar assets, or discounted future cash flow analyses.
Impairment of Equity Method Investments | CMS Energy also assesses equity method investments for impairment whenever there has been a decline in value that is other than temporary. This assessment requires CMS Energy to determine the fair value of the equity method investment. CMS Energy determines fair value using valuation methodologies, including discounted cash flows, and assesses the ability of the investee to sustain an earnings capacity that justifies the carrying amount of the investment. CMS Energy records an impairment if the fair value is less than the carrying amount and the decline in value is considered to be other than temporary.
Inventory - Gas and Coal | Inventory: CMS Energy and Consumers use the weighted-average cost method for valuing working gas, recoverable base gas in underground storage facilities, and materials and supplies inventory. CMS Energy and Consumers also use this method for valuing coal inventory, and they classify these amounts as generating plant fuel stock on their consolidated balance sheets.
Inventory - RECs and Emission Allowances | CMS Energy and Consumers account for RECs and emission allowances as inventory and use the weighted-average cost method to remove amounts from inventory. RECs and emission allowances are used to satisfy compliance obligations related to the generation of power. CMS Energy and Consumers classify these amounts within other assets on their consolidated balance sheets.
Inventory - Impairment | CMS Energy and Consumers evaluate inventory for impairment as required to ensure that its carrying value does not exceed the lower of cost or net realizable value.
MISO Transactions | MISO Transactions: MISO requires the submission of hourly day-ahead and real-time bids and offers for energy at locations across the MISO region. CMS Energy and Consumers account for MISO transactions on a net hourly basis in each of the real-time and day-ahead markets, netted across all MISO energy market locations. CMS Energy and Consumers record net hourly purchases in purchased and interchange power and net hourly sales in operating revenue on their consolidated statements of income. They record net billing adjustments upon receipt of settlement statements, record accruals for future net purchases and sales adjustments based on historical experience, and reconcile accruals to actual expenses and sales upon receipt of settlement statements.
Property Taxes | Property Taxes: Property taxes are based on the taxable value of Consumers’ real and personal property assessed by local taxing authorities. Consumers records property tax expense over the fiscal year of the taxing authority for which the taxes are levied. The deferred property tax balance represents the amount of Consumers’ accrued property tax that will be recognized over future governmental fiscal periods.
Renewable Energy Grant | Renewable Energy Grant: In 2013, Consumers received a renewable energy cash grant for Lake Winds® Energy Park under Section 1603 of the American Recovery and Reinvestment Tax Act of 2009. Upon receipt of the grant, Consumers recorded a regulatory liability, which Consumers is amortizing over the life of Lake Winds® Energy Park. Consumers presents the amortization as a reduction to maintenance and other operating expenses on its consolidated statements of income. Consumers recorded the deferred income taxes related to the grant as a reduction of the book basis of Lake Winds® Energy Park.
New Accounting Standards | Implementation of New Accounting Standards ASU 2014-09, Revenue from Contracts with Customers: This standard, which was effective on January 1, 2018 for CMS Energy and Consumers, provides new guidance for recognizing revenue from contracts with customers. A primary objective of the standard is to provide a single, comprehensive revenue recognition model that will be applied across entities, industries, and capital markets. The new guidance replaced most of the previous revenue recognition requirements in GAAP, although certain guidance specific to rate-regulated utilities was retained. CMS Energy and Consumers had the option to apply the standard retrospectively to all prior periods presented or retrospectively with the cumulative effect of the standard recorded as an adjustment to beginning retained earnings. They also had the option to apply the standard only to contracts existing on the effective date. CMS Energy and Consumers applied the standard retrospectively to contracts existing on the effective date, and recorded an immaterial cumulative-effect reduction to beginning retained earnings for certain contract costs that can no longer be deferred under the new guidance. The implementation of this standard did not have a material impact on CMS Energy’s or Consumers’ consolidated net income, cash flows, or financial position. CMS Energy and Consumers did not identify any significant changes to their revenue recognition practices that were required by the new guidance, but in accordance with the standard, they have provided additional disclosures about their revenues in Note 16, Revenue. ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities: This standard, which was effective on January 1, 2018 for CMS Energy and Consumers, is intended to improve the accounting for financial instruments. The standard requires investments in equity securities to be measured at fair value, with changes in fair value recognized in net income, except for certain investments such as those that qualify for equity-method accounting. The standard no longer permits unrealized gains and losses for certain equity investments to be recorded in AOCI. There are other targeted changes as well. Entities must apply the standard using a modified retrospective approach, with the cumulative effect of the standard recorded as an adjustment to beginning retained earnings. The implementation of the standard had no impact on CMS Energy’s consolidated financial statements. In accordance with the standard, as of January 1, 2018, Consumers removed a $19 million unrealized gain and the associated deferred taxes on its investment in CMS Energy common stock from AOCI and recorded the gain in retained earnings. In January 2018, Consumers transferred substantially all of its shares in CMS Energy common stock to a related charitable foundation and, in accordance with this standard, recognized all unrealized gains and losses on its remaining shares in net income for the year ended December 31, 2018. The accounting treatment for this investment is reflected in Consumers’ consolidated financial statements only, and had no impact on CMS Energy’s consolidated financial statements. For further details on CMS Energy’s and Consumers’ investments in debt and equity securities, see Note 7, Financial Instruments. ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income: This standard addresses the income tax effects stranded in AOCI as a result of the TCJA. Existing GAAP requires that the remeasurement of deferred tax assets and liabilities resulting from a change in tax laws or rates be presented in net income from continuing operations, even if the deferred taxes were associated with items that were originally recognized in AOCI. As a result, upon recognizing the effects of the TCJA, the tax effects of items in AOCI (referred to as stranded tax effects) no longer reflected the current income tax rate. To address this matter, this standard permits companies to reclassify to retained earnings the stranded tax effects of the TCJA. The standard is effective on January 1, 2019 for CMS Energy and Consumers, but early adoption is permitted. The new guidance is to be applied either in the period of adoption or retrospectively to each prior period in which the effect of the TCJA was recognized. CMS Energy and Consumers elected to adopt this standard early. Accordingly, as of January 1, 2018, CMS Energy reclassified $11 million of stranded tax effects from AOCI to retained earnings, which included $5 million reclassified at Consumers. At December 31, 2018, CMS Energy and Consumers did not have any material stranded tax effects remaining in AOCI. New Accounting Standards Not Yet Effective ASU 2016-02, Leases: This standard establishes a new accounting model for leases. The standard requires entities to recognize lease assets and liabilities on the balance sheet for all leases with a term of more than one year, including operating leases, which are not recorded on the balance sheet under existing standards. The new guidance also amends the definition of a lease to require that a lessee control the use of a specified asset, and not simply control or take the output of the asset. On the statement of income, leases that meet existing capital lease criteria will generally be accounted for under a financing model, while operating leases will generally be accounted for under a straight-line expense model. The standard is effective on January 1, 2019 for CMS Energy and Consumers, but early adoption is permitted. CMS Energy and Consumers did not adopt the standard early and will elect certain practical expedients permitted by the standard, under which they will not be required to perform lease assessments or reassessments for agreements existing on the effective date. They also will elect a transition method under which they will initially apply the standard on January 1, 2019, without adjusting amounts presented for prior periods. Under this method, the cumulative effect of applying the standard must be recorded as an adjustment to beginning retained earnings. Under the standard, CMS Energy and Consumers will recognize additional lease assets and liabilities on their consolidated balance sheets as of January 1, 2019 for their operating leases. CMS Energy and Consumers are finalizing their implementation of the standard and do not expect it to have a material impact on their consolidated net income or cash flows. See Note 10, Leases and Palisades Financing, for more information on CMS Energy’s and Consumers’ operating lease obligations. ASU 2016-13, Measurement of Credit Losses on Financial Instruments: This standard, which will be effective January 1, 2020 for CMS Energy and Consumers, provides new guidance for estimating and recording credit losses on financial instruments. The standard will apply to the recognition of loan losses at EnerBank as well as to the recognition of uncollectible accounts expense at Consumers. Entities will apply the standard using a modified retrospective approach, with a cumulative-effect adjustment recorded to beginning retained earnings on the effective date. CMS Energy and Consumers are evaluating the impact of the standard on their consolidated financial statements.
Allowance For Loan Losses Policy | During 2018, EnerBank purchased a portfolio of secured and unsecured consumer retail installment contracts with a principal value of $205 million at December 31, 2018. Authorized contractors pay fees to EnerBank to provide borrowers with same-as-cash, zero interest, or reduced interest loans. Unearned income associated with the loan fees, which is recorded as a reduction to notes receivable on CMS Energy’s consolidated balance sheets, was $102 million at December 31, 2018 and $84 million at December 31, 2017. The allowance for loan losses is a valuation allowance to reflect estimated credit losses. The allowance is increased by the provision for loan losses and decreased by loan charge-offs net of recoveries. Management estimates the allowance balance required by taking into consideration historical loan loss experience, the nature and volume of the portfolio, economic conditions, and other factors. Loan losses are charged against the allowance when the loss is confirmed, but no later than the point at which a loan becomes 120 days past due.
Asset Retirement Obligations Policy | CMS Energy and Consumers record the fair value of the cost to remove assets at the end of their useful lives, if there is a legal obligation to remove them. If a reasonable estimate of fair value cannot be made in the period in which the ARO is incurred, such as for assets with indeterminate lives, the liability is recognized when a reasonable estimate of fair value can be made. CMS Energy and Consumers have not recorded liabilities for assets that have immaterial cumulative disposal costs, such as substation batteries. CMS Energy and Consumers calculate the fair value of ARO liabilities using an expected present-value technique that reflects assumptions about costs and inflation, and uses a credit-adjusted risk-free rate to discount the expected cash flows. CMS Energy’s ARO liabilities are primarily at Consumers. As a regulated entity, Consumers defers the effects of any changes in assumptions on the fair values of its ARO liabilities, adjusting the associated regulatory assets or liabilities rather than recognizing such effects in earnings.
Income Tax Policy | CMS Energy and its subsidiaries file a consolidated U.S. federal income tax return as well as a Michigan Corporate Income Tax return for the unitary business group and various other state unitary group combined income tax returns. Income taxes are allocated based on each company’s separate taxable income in accordance with the CMS Energy tax sharing agreement.
Revenue | Electric and Gas Utilities Consumers Utility Revenue: Consumers recognizes revenue primarily from the sale of electric and gas utility services at tariff-based rates regulated by the MPSC. Consumers’ customer base consists of a mix of residential, commercial, and diversified industrial customers. Consumers’ tariff-based sales performance obligations are described below.
• | Consumers has performance obligations for the service of standing ready to deliver electricity or natural gas to customers, and it satisfies these performance obligations over time. Consumers recognizes revenue at a fixed rate as it provides these services. These arrangements generally do not have fixed terms and remain in effect as long as the customer consumes the utility service. The rates are set by the MPSC through the rate-making process and represent the stand-alone selling price of Consumers’ service to stand ready to deliver.
• | Consumers has performance obligations for the service of delivering the commodity of electricity or natural gas to customers, and it satisfies these performance obligations upon delivery. Consumers recognizes revenue at a price per unit of electricity or natural gas delivered, based on the tariffs established by the MPSC. These arrangements generally do not have fixed terms and remain in effect as long as the customer consumes the utility service. The rates are set by the MPSC through the rate-making process and represent the stand-alone selling price of a bundled product comprising the commodity, electricity or natural gas, and the service of delivering such commodity.
In some instances, Consumers has specific fixed-term contracts with large commercial and industrial customers to provide electricity or gas at certain tariff rates or to provide gas transportation services at contracted rates. The amount of electricity and gas to be delivered under these contracts and the associated future revenue to be received are generally dependent on the customers’ needs. Accordingly, Consumers recognizes revenues at the tariff or contracted rate as electricity or gas is delivered to the customer. Consumers also has other miscellaneous contracts with customers related to pole and other property rentals, appliance service plans, and utility contract work. Generally, these contracts are short term or evergreen in nature. EnerBank: EnerBank provides four types of unsecured consumer installment loans: same-as-cash, zero interest, reduced interest, and traditional. Under EnerBank’s same-as-cash programs, authorized contractors pay EnerBank a fee to provide a borrower with the option to pay off the loan interest-free during the same-as-cash period. EnerBank recognizes the fee on a straight-line basis over the same-as-cash period, which typically ranges from three to 24 months. If a borrower does not exercise its option to pay off its loan interest-free during the same-as-cash period, EnerBank charges the borrower accrued interest at the loan’s contractual rate on the outstanding balance from the origination date. Under the zero interest and reduced interest programs, authorized contractors pay EnerBank a fee to provide a borrower with no interest or reduced rates of interest for the entire term of the loan. EnerBank recognizes the fee using the interest method over the term of the loan, which ranges from one to 12 years. EnerBank recognizes interest income using the interest method and amortizes loan origination fees, net of certain direct origination costs, over the loan term. EnerBank ceases recognizing interest income when a loan loss is confirmed or when a loan becomes 120 days past due, at which time the loan principal is charged against the allowance for loan losses. At that time, EnerBank recognizes any interest accrued but not received for such loan losses as a reversal of interest income. Alternative-Revenue Programs: The energy waste reduction incentive mechanism provides a financial incentive if the energy savings of Consumers’ customers exceed annual targets established by the MPSC. The maximum incentive that Consumers may earn under this mechanism is 20 percent of the amount it spends on energy waste reduction programs. Consumers accounts for this program as an alternative-revenue program that meets the criteria for recognizing revenue related to the incentive as soon as energy savings exceed the annual targets established by the MPSC. Under a gas revenue decoupling mechanism authorized by the MPSC, Consumers is allowed to adjust future gas rates for differences between Consumers’ actual weather-normalized non‑fuel revenues and the revenues approved by the MPSC. Consumers accounts for this program as an alternative-revenue program that meets the criteria for recognizing the effects of decoupling adjustments on revenue as gas is delivered. Consumers does not reclassify revenue from its alternative-revenue programs to revenue from contracts with customers at the time the amounts are collected from customers. Accounts Receivable and Unbilled Revenues: Accounts receivable comprise trade receivables and unbilled receivables. CMS Energy and Consumers record their accounts receivable at cost, which approximates fair value. CMS Energy and Consumers establish an allowance for uncollectible accounts based on historical losses, management’s assessment of existing economic conditions, customer payment trends, and other factors. CMS Energy and Consumers assess late payment fees on trade receivables based on contractual past-due terms established with customers. CMS Energy and Consumers charge off accounts deemed uncollectible to operating expense. Uncollectible expense for CMS Energy, including Consumers, was $29 million for the year ended December 31, 2018. Uncollectible expense for Consumers was $29 million for the year ended December 31, 2018. Consumers’ customers are billed monthly in cycles having billing dates that do not generally coincide with the end of a calendar month. This results in customers having received electricity or natural gas that they have not been billed for as of the month-end. Consumers estimates its unbilled revenues by applying an average billed rate to total unbilled deliveries for each customer class. Unbilled revenues, which are recorded as accounts receivable on CMS Energy’s and Consumers’ consolidated balance sheets, were $409 million at December 31, 2018 and $481 million at December 31, 2017.
Cash and Cash Equivalents | Cash and Cash Equivalents: Cash and cash equivalents include short-term, highly liquid investments with original maturities of three months or less.
Restricted Cash and Cash Equivalents | Restricted Cash and Cash Equivalents: Restricted cash and cash equivalents are held primarily for the repayment of securitization bonds and funds held in escrow. Cash and cash equivalents may also be restricted to pay other contractual obligations such as leasing of coal railcars. These amounts are classified as current assets since they relate to payments that could or will occur within one year.
Consumers Energy Company |
Significant Accounting Policies [Line Items] |
Principles of Consolidation | Principles of Consolidation: CMS Energy and Consumers prepare their consolidated financial statements in conformity with GAAP. CMS Energy’s consolidated financial statements comprise CMS Energy, Consumers, CMS Enterprises, and all other entities in which CMS Energy has a controlling financial interest or is the primary beneficiary. Consumers’ consolidated financial statements comprise Consumers and all other entities in which it has a controlling financial interest or is the primary beneficiary. CMS Energy uses the equity method of accounting for investments in companies and partnerships that are not consolidated, where they have significant influence over operations and financial policies but are not the primary beneficiary. CMS Energy and Consumers eliminate intercompany transactions and balances.
Use of Estimates | Use of Estimates: CMS Energy and Consumers are required to make estimates using assumptions that may affect reported amounts and disclosures. Actual results could differ from those estimates.
Contingencies | Contingencies: CMS Energy and Consumers record estimated liabilities for contingencies on their consolidated financial statements when it is probable that a liability has been incurred and when the amount of loss can be reasonably estimated. For environmental remediation projects in which the timing of estimated expenditures is considered reliably determinable, CMS Energy and Consumers record the liability at its net present value, using a discount rate equal to the interest rate on monetary assets that are essentially risk-free and have maturities comparable to that of the environmental liability. CMS Energy and Consumers expense legal fees as incurred; fees incurred but not yet billed are accrued based on estimates of work performed.
Debt Issuance Costs, Discounts, Premiums, and Refinancing Costs | Debt Issuance Costs, Discounts, Premiums, and Refinancing Costs: Upon the issuance of long-term debt, CMS Energy and Consumers defer issuance costs, discounts, and premiums and amortize those amounts over the terms of the associated debt. Debt issuance costs are presented as a direct deduction from the carrying amount of long-term debt on the balance sheet. Upon the refinancing of long-term debt, Consumers, as a regulated entity, defers any remaining unamortized issuance costs, discounts, and premiums associated with the refinanced debt and amortizes those amounts over the term of the newly issued debt. For the non‑regulated portions of CMS Energy’s business, any remaining unamortized issuance costs, discounts, and premiums associated with extinguished debt are charged to earnings.
Derivative Instruments | Derivative Instruments: In order to support ongoing operations, CMS Energy and Consumers enter into contracts for the future purchase and sale of various commodities, such as electricity, natural gas, and coal. These forward contracts are generally long-term in nature and result in physical delivery of the commodity at a contracted price. Most of these contracts are not subject to derivative accounting for one or more of the following reasons:
• | they do not have a notional amount (that is, a number of units specified in a derivative instrument, such as MWh of electricity or bcf of natural gas)
• | they qualify for the normal purchases and sales exception
• | there is not an active market for the commodity
Consumers also uses FTRs to manage price risk related to electricity transmission congestion. An FTR is a financial instrument that entitles its holder to receive compensation or requires its holder to remit payment for congestion-related transmission charges. Consumers accounts for FTRs as derivatives. Additionally, CMS Energy uses interest rate swaps to manage its interest rate risk on certain long-term debt transactions. CMS Energy and Consumers record derivative contracts that do not qualify for the normal purchases and sales exception at fair value on their consolidated balance sheets. Each reporting period, the resulting asset or liability is adjusted to reflect any change in the fair value of the contract. At Consumers, changes in fair value are deferred as regulatory assets or liabilities. At CMS Energy, the changes are reported in earnings or, if the derivative qualifies for cash flow hedge accounting, in AOCI. For details regarding CMS Energy’s and Consumers’ derivative instruments recorded at fair value, see Note 6, Fair Value Measurements.
Impairment of Long-Lived Assets | Impairment of Long-Lived Assets and Equity Method Investments: CMS Energy and Consumers perform tests of impairment if certain triggering events occur or if there has been a decline in value that may be other than temporary. CMS Energy and Consumers evaluate long-lived assets held in use for impairment by calculating the undiscounted future cash flows expected to result from the use of the asset and its eventual disposition. If the undiscounted future cash flows are less than the carrying amount, CMS Energy and Consumers recognize an impairment loss equal to the amount by which the carrying amount exceeds the fair value. CMS Energy and Consumers estimate the fair value of the asset using quoted market prices, market prices of similar assets, or discounted future cash flow analyses.
Inventory - Gas and Coal | Inventory: CMS Energy and Consumers use the weighted-average cost method for valuing working gas, recoverable base gas in underground storage facilities, and materials and supplies inventory. CMS Energy and Consumers also use this method for valuing coal inventory, and they classify these amounts as generating plant fuel stock on their consolidated balance sheets.
Inventory - RECs and Emission Allowances | CMS Energy and Consumers account for RECs and emission allowances as inventory and use the weighted-average cost method to remove amounts from inventory. RECs and emission allowances are used to satisfy compliance obligations related to the generation of power. CMS Energy and Consumers classify these amounts within other assets on their consolidated balance sheets.
Inventory - Impairment | CMS Energy and Consumers evaluate inventory for impairment as required to ensure that its carrying value does not exceed the lower of cost or net realizable value.
MISO Transactions | MISO Transactions: MISO requires the submission of hourly day-ahead and real-time bids and offers for energy at locations across the MISO region. CMS Energy and Consumers account for MISO transactions on a net hourly basis in each of the real-time and day-ahead markets, netted across all MISO energy market locations. CMS Energy and Consumers record net hourly purchases in purchased and interchange power and net hourly sales in operating revenue on their consolidated statements of income. They record net billing adjustments upon receipt of settlement statements, record accruals for future net purchases and sales adjustments based on historical experience, and reconcile accruals to actual expenses and sales upon receipt of settlement statements.
Property Taxes | Property Taxes: Property taxes are based on the taxable value of Consumers’ real and personal property assessed by local taxing authorities. Consumers records property tax expense over the fiscal year of the taxing authority for which the taxes are levied. The deferred property tax balance represents the amount of Consumers’ accrued property tax that will be recognized over future governmental fiscal periods.
Renewable Energy Grant | Renewable Energy Grant: In 2013, Consumers received a renewable energy cash grant for Lake Winds® Energy Park under Section 1603 of the American Recovery and Reinvestment Tax Act of 2009. Upon receipt of the grant, Consumers recorded a regulatory liability, which Consumers is amortizing over the life of Lake Winds® Energy Park. Consumers presents the amortization as a reduction to maintenance and other operating expenses on its consolidated statements of income. Consumers recorded the deferred income taxes related to the grant as a reduction of the book basis of Lake Winds® Energy Park.
New Accounting Standards | Implementation of New Accounting Standards ASU 2014-09, Revenue from Contracts with Customers: This standard, which was effective on January 1, 2018 for CMS Energy and Consumers, provides new guidance for recognizing revenue from contracts with customers. A primary objective of the standard is to provide a single, comprehensive revenue recognition model that will be applied across entities, industries, and capital markets. The new guidance replaced most of the previous revenue recognition requirements in GAAP, although certain guidance specific to rate-regulated utilities was retained. CMS Energy and Consumers had the option to apply the standard retrospectively to all prior periods presented or retrospectively with the cumulative effect of the standard recorded as an adjustment to beginning retained earnings. They also had the option to apply the standard only to contracts existing on the effective date. CMS Energy and Consumers applied the standard retrospectively to contracts existing on the effective date, and recorded an immaterial cumulative-effect reduction to beginning retained earnings for certain contract costs that can no longer be deferred under the new guidance. The implementation of this standard did not have a material impact on CMS Energy’s or Consumers’ consolidated net income, cash flows, or financial position. CMS Energy and Consumers did not identify any significant changes to their revenue recognition practices that were required by the new guidance, but in accordance with the standard, they have provided additional disclosures about their revenues in Note 16, Revenue. ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities: This standard, which was effective on January 1, 2018 for CMS Energy and Consumers, is intended to improve the accounting for financial instruments. The standard requires investments in equity securities to be measured at fair value, with changes in fair value recognized in net income, except for certain investments such as those that qualify for equity-method accounting. The standard no longer permits unrealized gains and losses for certain equity investments to be recorded in AOCI. There are other targeted changes as well. Entities must apply the standard using a modified retrospective approach, with the cumulative effect of the standard recorded as an adjustment to beginning retained earnings. The implementation of the standard had no impact on CMS Energy’s consolidated financial statements. In accordance with the standard, as of January 1, 2018, Consumers removed a $19 million unrealized gain and the associated deferred taxes on its investment in CMS Energy common stock from AOCI and recorded the gain in retained earnings. In January 2018, Consumers transferred substantially all of its shares in CMS Energy common stock to a related charitable foundation and, in accordance with this standard, recognized all unrealized gains and losses on its remaining shares in net income for the year ended December 31, 2018. The accounting treatment for this investment is reflected in Consumers’ consolidated financial statements only, and had no impact on CMS Energy’s consolidated financial statements. For further details on CMS Energy’s and Consumers’ investments in debt and equity securities, see Note 7, Financial Instruments. ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income: This standard addresses the income tax effects stranded in AOCI as a result of the TCJA. Existing GAAP requires that the remeasurement of deferred tax assets and liabilities resulting from a change in tax laws or rates be presented in net income from continuing operations, even if the deferred taxes were associated with items that were originally recognized in AOCI. As a result, upon recognizing the effects of the TCJA, the tax effects of items in AOCI (referred to as stranded tax effects) no longer reflected the current income tax rate. To address this matter, this standard permits companies to reclassify to retained earnings the stranded tax effects of the TCJA. The standard is effective on January 1, 2019 for CMS Energy and Consumers, but early adoption is permitted. The new guidance is to be applied either in the period of adoption or retrospectively to each prior period in which the effect of the TCJA was recognized. CMS Energy and Consumers elected to adopt this standard early. Accordingly, as of January 1, 2018, CMS Energy reclassified $11 million of stranded tax effects from AOCI to retained earnings, which included $5 million reclassified at Consumers. At December 31, 2018, CMS Energy and Consumers did not have any material stranded tax effects remaining in AOCI. New Accounting Standards Not Yet Effective ASU 2016-02, Leases: This standard establishes a new accounting model for leases. The standard requires entities to recognize lease assets and liabilities on the balance sheet for all leases with a term of more than one year, including operating leases, which are not recorded on the balance sheet under existing standards. The new guidance also amends the definition of a lease to require that a lessee control the use of a specified asset, and not simply control or take the output of the asset. On the statement of income, leases that meet existing capital lease criteria will generally be accounted for under a financing model, while operating leases will generally be accounted for under a straight-line expense model. The standard is effective on January 1, 2019 for CMS Energy and Consumers, but early adoption is permitted. CMS Energy and Consumers did not adopt the standard early and will elect certain practical expedients permitted by the standard, under which they will not be required to perform lease assessments or reassessments for agreements existing on the effective date. They also will elect a transition method under which they will initially apply the standard on January 1, 2019, without adjusting amounts presented for prior periods. Under this method, the cumulative effect of applying the standard must be recorded as an adjustment to beginning retained earnings. Under the standard, CMS Energy and Consumers will recognize additional lease assets and liabilities on their consolidated balance sheets as of January 1, 2019 for their operating leases. CMS Energy and Consumers are finalizing their implementation of the standard and do not expect it to have a material impact on their consolidated net income or cash flows. See Note 10, Leases and Palisades Financing, for more information on CMS Energy’s and Consumers’ operating lease obligations. ASU 2016-13, Measurement of Credit Losses on Financial Instruments: This standard, which will be effective January 1, 2020 for CMS Energy and Consumers, provides new guidance for estimating and recording credit losses on financial instruments. The standard will apply to the recognition of loan losses at EnerBank as well as to the recognition of uncollectible accounts expense at Consumers. Entities will apply the standard using a modified retrospective approach, with a cumulative-effect adjustment recorded to beginning retained earnings on the effective date. CMS Energy and Consumers are evaluating the impact of the standard on their consolidated financial statements.
Asset Retirement Obligations Policy | CMS Energy and Consumers record the fair value of the cost to remove assets at the end of their useful lives, if there is a legal obligation to remove them. If a reasonable estimate of fair value cannot be made in the period in which the ARO is incurred, such as for assets with indeterminate lives, the liability is recognized when a reasonable estimate of fair value can be made. CMS Energy and Consumers have not recorded liabilities for assets that have immaterial cumulative disposal costs, such as substation batteries. CMS Energy and Consumers calculate the fair value of ARO liabilities using an expected present-value technique that reflects assumptions about costs and inflation, and uses a credit-adjusted risk-free rate to discount the expected cash flows. CMS Energy’s ARO liabilities are primarily at Consumers. As a regulated entity, Consumers defers the effects of any changes in assumptions on the fair values of its ARO liabilities, adjusting the associated regulatory assets or liabilities rather than recognizing such effects in earnings.
Income Tax Policy | CMS Energy and its subsidiaries file a consolidated U.S. federal income tax return as well as a Michigan Corporate Income Tax return for the unitary business group and various other state unitary group combined income tax returns. Income taxes are allocated based on each company’s separate taxable income in accordance with the CMS Energy tax sharing agreement.
Revenue | Electric and Gas Utilities Consumers Utility Revenue: Consumers recognizes revenue primarily from the sale of electric and gas utility services at tariff-based rates regulated by the MPSC. Consumers’ customer base consists of a mix of residential, commercial, and diversified industrial customers. Consumers’ tariff-based sales performance obligations are described below.
• | Consumers has performance obligations for the service of standing ready to deliver electricity or natural gas to customers, and it satisfies these performance obligations over time. Consumers recognizes revenue at a fixed rate as it provides these services. These arrangements generally do not have fixed terms and remain in effect as long as the customer consumes the utility service. The rates are set by the MPSC through the rate-making process and represent the stand-alone selling price of Consumers’ service to stand ready to deliver.
• | Consumers has performance obligations for the service of delivering the commodity of electricity or natural gas to customers, and it satisfies these performance obligations upon delivery. Consumers recognizes revenue at a price per unit of electricity or natural gas delivered, based on the tariffs established by the MPSC. These arrangements generally do not have fixed terms and remain in effect as long as the customer consumes the utility service. The rates are set by the MPSC through the rate-making process and represent the stand-alone selling price of a bundled product comprising the commodity, electricity or natural gas, and the service of delivering such commodity.
In some instances, Consumers has specific fixed-term contracts with large commercial and industrial customers to provide electricity or gas at certain tariff rates or to provide gas transportation services at contracted rates. The amount of electricity and gas to be delivered under these contracts and the associated future revenue to be received are generally dependent on the customers’ needs. Accordingly, Consumers recognizes revenues at the tariff or contracted rate as electricity or gas is delivered to the customer. Consumers also has other miscellaneous contracts with customers related to pole and other property rentals, appliance service plans, and utility contract work. Generally, these contracts are short term or evergreen in nature. EnerBank: EnerBank provides four types of unsecured consumer installment loans: same-as-cash, zero interest, reduced interest, and traditional. Under EnerBank’s same-as-cash programs, authorized contractors pay EnerBank a fee to provide a borrower with the option to pay off the loan interest-free during the same-as-cash period. EnerBank recognizes the fee on a straight-line basis over the same-as-cash period, which typically ranges from three to 24 months. If a borrower does not exercise its option to pay off its loan interest-free during the same-as-cash period, EnerBank charges the borrower accrued interest at the loan’s contractual rate on the outstanding balance from the origination date. Under the zero interest and reduced interest programs, authorized contractors pay EnerBank a fee to provide a borrower with no interest or reduced rates of interest for the entire term of the loan. EnerBank recognizes the fee using the interest method over the term of the loan, which ranges from one to 12 years. EnerBank recognizes interest income using the interest method and amortizes loan origination fees, net of certain direct origination costs, over the loan term. EnerBank ceases recognizing interest income when a loan loss is confirmed or when a loan becomes 120 days past due, at which time the loan principal is charged against the allowance for loan losses. At that time, EnerBank recognizes any interest accrued but not received for such loan losses as a reversal of interest income. Alternative-Revenue Programs: The energy waste reduction incentive mechanism provides a financial incentive if the energy savings of Consumers’ customers exceed annual targets established by the MPSC. The maximum incentive that Consumers may earn under this mechanism is 20 percent of the amount it spends on energy waste reduction programs. Consumers accounts for this program as an alternative-revenue program that meets the criteria for recognizing revenue related to the incentive as soon as energy savings exceed the annual targets established by the MPSC. Under a gas revenue decoupling mechanism authorized by the MPSC, Consumers is allowed to adjust future gas rates for differences between Consumers’ actual weather-normalized non‑fuel revenues and the revenues approved by the MPSC. Consumers accounts for this program as an alternative-revenue program that meets the criteria for recognizing the effects of decoupling adjustments on revenue as gas is delivered. Consumers does not reclassify revenue from its alternative-revenue programs to revenue from contracts with customers at the time the amounts are collected from customers. Accounts Receivable and Unbilled Revenues: Accounts receivable comprise trade receivables and unbilled receivables. CMS Energy and Consumers record their accounts receivable at cost, which approximates fair value. CMS Energy and Consumers establish an allowance for uncollectible accounts based on historical losses, management’s assessment of existing economic conditions, customer payment trends, and other factors. CMS Energy and Consumers assess late payment fees on trade receivables based on contractual past-due terms established with customers. CMS Energy and Consumers charge off accounts deemed uncollectible to operating expense. Uncollectible expense for CMS Energy, including Consumers, was $29 million for the year ended December 31, 2018. Uncollectible expense for Consumers was $29 million for the year ended December 31, 2018. Consumers’ customers are billed monthly in cycles having billing dates that do not generally coincide with the end of a calendar month. This results in customers having received electricity or natural gas that they have not been billed for as of the month-end. Consumers estimates its unbilled revenues by applying an average billed rate to total unbilled deliveries for each customer class. Unbilled revenues, which are recorded as accounts receivable on CMS Energy’s and Consumers’ consolidated balance sheets, were $409 million at December 31, 2018 and $481 million at December 31, 2017.
Cash and Cash Equivalents | Cash and Cash Equivalents: Cash and cash equivalents include short-term, highly liquid investments with original maturities of three months or less.
Restricted Cash and Cash Equivalents | Restricted Cash and Cash Equivalents: Restricted cash and cash equivalents are held primarily for the repayment of securitization bonds and funds held in escrow. Cash and cash equivalents may also be restricted to pay other contractual obligations such as leasing of coal railcars. These amounts are classified as current assets since they relate to payments that could or will occur within one year.

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