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Intangible Assets - Schedule of Amortization Expense of Intangible Assets (Detail) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]    
2019 $ 133  
2020 113  
2021 129  
2022 159  
2023 315  
Total intangible assets $ 849 $ 506