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Fair Value Measurements - Additional Information (Details) - USD ($)
$ in Thousands
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and restricted cash $ 30,789 $ 20,708 $ 5,797
Level 1      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Cash and restricted cash $ 30,800 $ 20,700