cm:Level3TextBlock: us-gaap:ScheduleOfLongTermContractsForPurchaseOfElectricPowerTextBlock
| Schedule of Long-term Contracts for Purchase of Electric Power [Table Text Block] |
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| Tabular disclosure of information concerning the terms and significance of long term contracts to purchase power (generally referred to as purchase power agreements (PPAs) or power sale agreements (PSAs)) including date of contract expiration, share of plant output being purchased, estimated annual cost, annual minimum debt service payment required and amount of related long-term debt or lease obligations outstanding. |
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