Notes Receivable (Schedule Of Current And Non-Current Notes Receivable) (Details) - USD ($) $ in Millions |
Mar. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Current | ||
| EnerBank notes receivable, net of allowance for loan losses | $ 241 | $ 223 |
| Non‑current | ||
| Total notes receivable | 2,444 | 2,500 |
| Consumers Energy Company | ||
| Current | ||
| DB SERP note receivable – related party | 7 | 7 |
| Non‑current | ||
| DB SERP note receivable – related party | 96 | 96 |
| Total notes receivable | 103 | 103 |
| EnerBank | ||
| Current | ||
| EnerBank notes receivable, net of allowance for loan losses | 241 | 242 |
| Non‑current | ||
| EnerBank notes receivable, net of allowance for loan losses | 2,203 | 2,258 |
| EnerBank | Receivables Excluding Held for Sale | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Loans and Leases Receivable, Deferred Income | 130 | 134 |
| Current | ||
| EnerBank notes receivable, net of allowance for loan losses | 241 | 223 |
| EnerBank | Receivables Held for Sale | ||
| Current | ||
| EnerBank notes receivable, net of allowance for loan losses | $ 0 | $ 19 |