Annual report pursuant to Section 13 and 15(d)

Condensed Financial Statements - Summary of Certain Statements of Operations Amounts (Detail)

v3.19.1
Condensed Financial Statements - Summary of Certain Statements of Operations Amounts (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Stock compensation expense $ 4,385 $ 12,091 $ 948
Depreciation expense, including amortization of assets under capital lease 1,081 551 345
Research and Development [Member]      
Stock compensation expense 629 6,086 928
General and Administrative Expense [Member]      
Stock compensation expense $ 3,756 $ 6,005 $ 20