Number of units retired.

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- Definition

Amount of public utility's approved temporary rate increase (decrease) by regulatory agency.

+ References

No definition available.

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- Definition

The amount requested from regulatory entity for the recovery/collection from customers.

+ References

No definition available.

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- Definition

The revenue requirement needed to recover the cost of base assets.

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No definition available.

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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2921-110230

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

+ References

No definition available.

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

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- Definition

Percentage of public utility's requested return on equity.

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- Definition

The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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Regulatory Matters (Narrative) (Details) $ in Millions	1 Months Ended						6 Months Ended
Regulatory Matters (Narrative) (Details) $ in Millions	Apr. 30, 2016 USD ($) item	Jan. 31, 2016 USD ($)	Nov. 30, 2015 USD ($)	Jul. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)
Public Utilities, General Disclosures [Line Items]
Regulatory liability current							$ 78	$ 82
Electric Transmission [Member]
Public Utilities, General Disclosures [Line Items]
Change in net plant, property, and equipment	$ 34
Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liability current							78	82
Electric Rate Case [Member] \| Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Annual rate increase requested						$ 163
Rate of return on equity requested						10.70%
Annual rate increase self-implemented					$ 110
Annual rate increase authorized	$ 126
Rate of return on equity authorized			10.30%
Temporary rate increase			$ 165
Number of units retired \| item	7
Electric Rate Case [Member] \| Self-Implemented Rate Refunds [Member] \| Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liability current							1
Gas Rate Case [Member] \| Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Annual rate increase requested				$ 85
Rate of return on equity requested				10.70%
Annual rate increase self-implemented		$ 60
Annual rate increase authorized	$ 40
Gas Rate Case [Member] \| Self-Implemented Rate Refunds [Member] \| Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory liability current							10
Energy Optimization Plan Incentive [Member] \| Consumers Energy Company [Member]
Public Utilities, General Disclosures [Line Items]
Requested recovery/collection								$ 18
Current FERC Revenue Requirement [Member] \| Electric Transmission [Member]
Public Utilities, General Disclosures [Line Items]
Revenue requirement							9
METC Proposed FERC Revenue Requirement [Member] \| Electric Transmission [Member]
Public Utilities, General Disclosures [Line Items]
Revenue requirement							$ 6