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Noncontrolling Interests - Additional information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Noncontrolling Interests [Line Items] |  |  |
Capital contributions to joint venture | $ 0 |  |
Net loss attributable to noncontrolling interest | (1,476,000) | $ 207,000 | $ 0
Huen Electric Inc [Member] |  |  |
Noncontrolling Interests [Line Items] |  |  |
Distributions to partners | $ 0 |  |

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