cm:Level3TextBlock: us-gaap:PublicUtilitiesGeneralDisclosuresTableTextBlock
| Public Utilities General Disclosures [Table Text Block] |
| us-gaap:PublicUtilitiesGeneralDisclosuresTableTextBlock |
| Tabular disclosure of regulation for public utility entities, including, but not limited to, rate requests, decommissioning costs and the amount of allowance for earnings on equity capitalized for rate making purposes. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:PublicUtilitiesGeneralDisclosuresTableTextBlock |