Summary of Significant Accounting Policies - Energy Assets (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Revenue, Major Customer [Line Items] | |||
| Interest costs capitalized | $ 2,966,000 | $ 3,817,000 | $ 4,256,000 |
| Grant proceeds | 784,000 | ||
| Deferred grant income | 6,885,000 | 6,637,000 | |
| Rebates from utility company | 0 | $ 0 | $ 0 |
| United States | |||
| Revenue, Major Customer [Line Items] | |||
| Deferred grant income | $ 6,086,000 | ||
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- Definition Grant Proceeds No definition available.
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- Definition Rebates from Utility Company No definition available.
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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 of interest capitalized during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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