| Component: (Network and Table) | |
|---|---|
| Network | 40802 - Disclosure - Plant, Property, and Equipment (Schedule of Capital Leased Asssets) (Details) (http://www.cmsenergy.com/2009-06-30/role/DisclosurePlantPropertyAndEquipmentScheduleOfCapitalLeasedAsssetsDetails) |
| Table | Statement [Table] |
| Reporting Entity [Axis] | 0000811156 (http://www.sec.gov/CIK) |
| Legal Entity [Axis] | Consumers Energy Company [Member] |
| Statement [Line Items] | Period [Axis] | |
|---|---|---|
2013-01-01 - 2013-12-31 | 2012-01-01 - 2012-12-31 | |
Balance at beginning of period | 285,000,000 | 280,000,000 |
Capital Leased Assets, Gross, Additions | 12,000,000 | 9,000,000 |
Capital Leased Assets, Gross, Disposals and Transfers | (6,000,000) | (4,000,000) |
Balance at end of period | 291,000,000 | 285,000,000 |
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation | 124,000,000 | 108,000,000 |