Summary of Significant Accounting Policies - Energy Assets and Asset Retirement Obligations (Details) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Dec. 31, 2016 |
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| Accounting Policies [Abstract] | |||||
| Interest costs capitalized | $ 925,000 | $ 289,000 | $ 3,452,000 | $ 616,000 | |
| Property, Plant and Equipment [Line Items] | |||||
| Capital lease assets, net | 4,830,000 | $ 4,830,000 | $ 5,018,000 | ||
| Minimum qualifying operating period for prorated repayments of grants | 5 years | ||||
| Deferred grant income | 7,326,000 | $ 7,326,000 | 7,739,000 | ||
| Asset retirement obligation | 0 | ||||
| Assets Held under Capital Leases | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Capital lease assets | 30,430,000 | 30,430,000 | 15,640,000 | ||
| Less - accumulated depreciation and amortization | $ (1,630,000) | $ (1,630,000) | $ (744,000) | ||
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- Definition Government Grant, Qualification Requirement, Prorated Repayment Effective Period from Date Placed in Service No definition available.
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- References No definition available.
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- Definition Amount of accumulated depreciation, depletion and amortization for 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 carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of interest capitalized during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unearned revenue or income classified as other, expected to be taken into income after one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. 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 after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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