Energy Assets - Additional Information (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Property, Plant and Equipment [Line Items] | |||
| Project assets, net | $ 356,443,000 | $ 319,758,000 | |
| Capital lease assets | 38,725,000 | 15,640,000 | |
| Less - accumulated depreciation and amortization | (2,049,000) | (744,000) | |
| Capital lease assets, net | 36,676,000 | 14,896,000 | |
| Rebates from utility company | 0 | 0 | $ 0 |
| Project asset depreciation | 21,648,000 | 19,377,000 | 16,911,000 |
| Depreciation and amortization expense on capital lease assets | 1,305,000 | 570,000 | $ 174,000 |
| Renewal Energy Program | |||
| Property, Plant and Equipment [Line Items] | |||
| Energy assets | 488,818,000 | 431,361,000 | |
| Less - accumulated depreciation and amortization | (132,375,000) | (111,603,000) | |
| Project assets, net | $ 356,443,000 | $ 319,758,000 | |
| X | ||||||||||
- Definition Rebates from Utility Company No definition available.
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- Definition Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The charge for the use of long-lived depreciable capital leased assets for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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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- Definition Amount of operating expense for depreciation and amortization of regulated operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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