Basis of Presentation and Summary of Significant Accounting Policies - Impairment of long-lived assets (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Basis of Presentation and Summary of Significant Accounting Policies | |||
| Impairment of long-lived assets | $ 0 | $ 0 | $ 0 |
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- References No definition available.
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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