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Fair Value Measurements (Tables) | 9 Months Ended
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Sep. 30, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Assets And Liabilities Measured At Fair Value On A Recurring Basis | Presented in the following table are CMS Energy’s and Consumers’ assets and liabilities recorded at fair value on a recurring basis:
In Millions |
| CMS Energy, including Consumers |  | Consumers
| September 30 2018 |  | December 31 2017 |  |  | September 30 2018 |  | December 31 2017 |
Assets 1 |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 139 |  |  | $ | 74 |  |  |  | $ | — |  |  | $ | — |
Restricted cash equivalents |  | 42 |  |  | 17 |  |  |  | 28 |  |  | 17 |
CMS Energy common stock |  | — |  |  | — |  |  |  | 1 |  |  | 21 |
Nonqualified deferred compensation plan assets |  | 14 |  |  | 14 |  |  |  | 11 |  |  | 10 |
DB SERP |  |  |  |  |  |  |  |  |
Cash equivalents |  | 1 |  |  | 5 |  |  |  | 1 |  |  | 4 |
Debt securities |  | — |  |  | 141 |  |  |  | — |  |  | 102 |
Derivative instruments |  |  |  |  |  |  |  |  |
Commodity contracts |  | 1 |  |  | 1 |  |  |  | 1 |  |  | 1 |
Total |  | $ | 197 |  |  | $ | 252 |  |  |  | $ | 42 |  |  | $ | 155 |
Liabilities 1 |  |  |  |  |  |  |  |  |
Nonqualified deferred compensation plan liabilities |  | $ | 14 |  |  | $ | 14 |  |  |  | $ | 11 |  |  | $ | 10 |
Derivative instruments |  |  |  |  |  |  |  |  |
Commodity contracts |  | 1 |  |  | 1 |  |  |  | 1 |  |  | — |
Total |  | $ | 15 |  |  | $ | 15 |  |  |  | $ | 12 |  |  | $ | 10 |
1 | All assets and liabilities were classified as Level 1 with the exception of some commodity contracts, which were classified as Level 3.
Consumers Energy Company |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Assets And Liabilities Measured At Fair Value On A Recurring Basis | Presented in the following table are CMS Energy’s and Consumers’ assets and liabilities recorded at fair value on a recurring basis:
In Millions |
| CMS Energy, including Consumers |  | Consumers
| September 30 2018 |  | December 31 2017 |  |  | September 30 2018 |  | December 31 2017 |
Assets 1 |  |  |  |  |  |  |  |  |
Cash equivalents |  | $ | 139 |  |  | $ | 74 |  |  |  | $ | — |  |  | $ | — |
Restricted cash equivalents |  | 42 |  |  | 17 |  |  |  | 28 |  |  | 17 |
CMS Energy common stock |  | — |  |  | — |  |  |  | 1 |  |  | 21 |
Nonqualified deferred compensation plan assets |  | 14 |  |  | 14 |  |  |  | 11 |  |  | 10 |
DB SERP |  |  |  |  |  |  |  |  |
Cash equivalents |  | 1 |  |  | 5 |  |  |  | 1 |  |  | 4 |
Debt securities |  | — |  |  | 141 |  |  |  | — |  |  | 102 |
Derivative instruments |  |  |  |  |  |  |  |  |
Commodity contracts |  | 1 |  |  | 1 |  |  |  | 1 |  |  | 1 |
Total |  | $ | 197 |  |  | $ | 252 |  |  |  | $ | 42 |  |  | $ | 155 |
Liabilities 1 |  |  |  |  |  |  |  |  |
Nonqualified deferred compensation plan liabilities |  | $ | 14 |  |  | $ | 14 |  |  |  | $ | 11 |  |  | $ | 10 |
Derivative instruments |  |  |  |  |  |  |  |  |
Commodity contracts |  | 1 |  |  | 1 |  |  |  | 1 |  |  | — |
Total |  | $ | 15 |  |  | $ | 15 |  |  |  | $ | 12 |  |  | $ | 10 |
1 | All assets and liabilities were classified as Level 1 with the exception of some commodity contracts, which were classified as Level 3.

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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258 + Details
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