Short-Term Investments (Tables)

12 Months Ended

Dec. 31, 2020

Investments Debt And Equity Securities [Abstract]

Summary of Amortized Cost and Estimated Fair Value of Marketable Securities

The following table summarizes the amortized cost and estimated fair value of the Company’s marketable securities, which are considered to be available-for-sale investments and were included in short-term investments on the consolidated balance sheets:

	December 31, 2020
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government treasury securities	$	233,687	$	—	$	(24	)	$	233,663
Totals	$	233,687	$	—	$	(24	)	$	233,663
	December 31, 2019
(in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
U.S. government treasury securities	$	64,925	$	68	$	—		$	64,993
Totals	$	64,925	$	68	$	—		$	64,993