Quarterly report pursuant to Section 13 or 15(d)

Short-term Investments - Summary of Debt Securities by Major Security Type (Detail)

v3.19.3
Short-term Investments - Summary of Debt Securities by Major Security Type (Detail)
$ in Thousands
Jun. 30, 2019
USD ($)
Schedule Of Available For Sale Securities [Line Items]  
Amortized cost $ 36,550
Gross unrealized gains 51
Fair value 36,601
U.S. Government Securities [Member]  
Schedule Of Available For Sale Securities [Line Items]  
Amortized cost 19,877
Gross unrealized gains 46
Fair value 19,923
U.S. T-bills [Member]  
Schedule Of Available For Sale Securities [Line Items]  
Amortized cost 9,968
Gross unrealized gains 3
Fair value 9,971
U.S. Agency Securities [Member]  
Schedule Of Available For Sale Securities [Line Items]  
Amortized cost 6,705
Gross unrealized gains 2
Fair value $ 6,707