Quarterly report pursuant to Section 13 or 15(d)

Marketable Securities - Summary of Marketable Securities (Detail)

v3.19.1
Marketable Securities - Summary of Marketable Securities (Detail) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 14,662 $ 29,144
Unrealized Gains 3 0
Unrealized Losses 0 (17)
Estimated Fair Value 14,665 29,127
Corporate debt securities 1 or less years of maturity [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 14,662 29,144
Unrealized Gains 3 0
Unrealized Losses 0 (17)
Estimated Fair Value $ 14,665 $ 29,127