| Energy Assets - Energy Assets (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019 | ||
|---|---|---|---|---|
| Property, Plant and Equipment [Line Items] | ||||
| Energy assets, net | [1] | $ 670,139 | $ 579,461 | |
| Energy Assets | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Energy assets | 885,148 | 767,331 | ||
| Less - accumulated depreciation and amortization | (215,009) | (187,870) | ||
| Energy assets, net | $ 670,139 | $ 579,461 | ||
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- Definition 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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- Definition Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of accumulated depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other. No definition available. 
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- Definition Amount after depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other. No definition available. 
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- Details 
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