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Retirement Benefits (Schedule Of Net Loss And Prior Service Cost (Credit) That Will Be Amortized In 2015) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2015 USD ($)
Pension Plan [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Regulatory asset | $ 72
AOCI | 1
Pension Plan [Member] | Consumers Energy Company [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Regulatory asset | 72
OPEB [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Regulatory asset | (18)
AOCI | (2)
OPEB [Member] | Consumers Energy Company [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Regulatory asset | $ (18)

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- Definition Defined benefit plan, amount to be amortized from (to) regulatory assets in next fiscal year. + References No definition available. + Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation). + References No definition available. + Details
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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. + Details
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- Details
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