Notes Receivable (Schedule Of Current And Non-Current Notes Receivable) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current
Current notes receivable	$ 233	$ 198
Non-current
Total notes receivable	1,857	1,371
Consumers Energy Company
Current
Current notes receivable	0	17
DB SERP note receivable – related party	7	0
Non-current
Accounts and notes receivable – related parties	99	0
Total notes receivable	106	17
EnerBank
Non-current
Notes receivable	1,624	1,171
EnerBank notes receivable, net of allowance for loan losses \| EnerBank
Current
Current notes receivable	233	178
EnerBank notes receivable held for sale \| EnerBank
Current
Current notes receivable	0	2
Michigan tax settlement
Current
Current notes receivable	0	20
Michigan tax settlement \| Consumers Energy Company
Current
Current notes receivable	$ 0	$ 17

An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

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