NATURE OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES - Income Taxes (Details) - subsidiary	Sep. 30, 2021	Mar. 31, 2021
Scrubgrass Generating Company, L.P.
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of subsidiaries	2	2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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