Stock-Based Compensation (Schedule Of Compensation Cost For Share-Based Payment Arrangements, Allocation Of Share-Based Compensation Costs By Plan) (Details) - Restricted stock - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares that vested during the year	$ 27	$ 37	$ 31
Compensation expense recognized	17	17	16
Income tax benefit recognized	1	7	7
Consumers Energy Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares that vested during the year	26	35	30
Compensation expense recognized	16	16	16
Income tax benefit recognized	$ 1	$ 7	$ 6

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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