SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - Genco $ in Millions	Mar. 31, 2019 USD ($) MW
Power Generation Capacity Megawatts \| MW	605
Property, Plant and Equipment, Net \| $	$ 499

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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