Annual report pursuant to Section 13 and 15(d)

Financial Instruments - Schedule of Cash and Cash Equivalents (Detail)

v3.20.4
Financial Instruments - Schedule of Cash and Cash Equivalents (Detail) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]    
Cash and cash equivalents $ 114,817 $ 44,065
Total Cash and Debt Securities 114,817 44,065
Total Fair Value, Cash and Debt Securities 114,817 44,065
Cash [Member]    
Schedule Of Available For Sale Securities [Line Items]    
Cash and cash equivalents 44,795 23,710
Fair Value, Cash 44,795 23,710
Level 1 [Member] | Money Market Funds [Member]    
Schedule Of Available For Sale Securities [Line Items]    
Cash and cash equivalents 70,022 20,355
Cash and cash equivalents gross before unrealized losses 70,022 20,355
Fair Value, Cash $ 70,022 $ 20,355