Annual report pursuant to Section 13 and 15(d)

Marketable Securities - Additional Information (Detail)

v3.21.1
Marketable Securities - Additional Information (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Asset-backed Securities [Member] | Maximum [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Remaining contractual maturities of marketable securities 1 year 1 year
U.S. and Foreign Commercial Paper [Member] | Maximum [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Remaining contractual maturities of marketable securities 1 year 1 year
U.S. and Foreign Corporate Debt Securities [Member] | Maximum [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Remaining contractual maturities of marketable securities 1 year 1 year
U.S. Treasury Securities [Member] | Maximum [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Remaining contractual maturities of marketable securities 1 year 1 year
Debt Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Realized gains and losses $ 0 $ 0
Marketable investments continuous unrealized loss position $ 0 $ 0