Nature of Operations and Basis of Consolidation (Details) $ in Millions	3 Months Ended
Sep. 30, 2020 USD ($) watts	Dec. 31, 2019 customers
Number of customers \| customers		734,800
Number of megawatts of qualifying facility \| watts	35
Estimated aggregate gross contractual payments for qualifying facilities through 2024	$ 123.9
Goodwill, Impairment Loss	$ 0.0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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