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Operations and Significant Accounting Policies - Non-Controlling Interest (Details)	3 Months Ended
	Mar. 31, 2021 MW
South Peak [Member]
Non-Controlling Interest Details [Line Items]
Generating Capacity Subject to Tax Equity Financing	80
Glen Ullin Energy Center [Member]
Non-Controlling Interest Details [Line Items]
Generating Capacity Subject to Tax Equity Financing	106
Nobles 2 [Member]
Non-Controlling Interest Details [Line Items]
Generating Capacity Subject to Tax Equity Financing	250
Diamond Spring
Non-Controlling Interest Details [Line Items]
Generating Capacity Subject to Tax Equity Financing	303

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