Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Summary of Marketable Securities

Marketable securities at December 31, 2021 consisted of the following:

(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:
U.S. Treasuries	$	269,109	$	—	$	(36)	$	269,073
Government securities	17,764		1		(10)		17,755
Corporate debt securities	530,490		3		(429)		530,064
Total Current	817,363		4		(475)		816,892
Non-current:
U.S. Treasuries	40,607		—		(23)		40,584
Government securities	148,820		—		(470)		148,350
Corporate debt securities	77,675		—		(234)		77,441
Total Non-current	267,102		—		(727)		266,375
Total marketable securities	$	1,084,465	$	4	$	(1,202)	$	1,083,267

Marketable securities at December 31, 2020 consisted of the following:

(In thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:
U.S. Treasuries	$	113,559	$	134	$	(21)	$	113,672
Government securities	108,263		37		(8)		108,292
Corporate debt securities	223,461		140		(72)		223,529
Total Current	445,283		311		(101)		445,493
Non-current:
U.S. Treasuries	15,147		—		(10)		15,137
Government securities	26,831		8		—		26,839
Corporate debt securities	55,735		2		(105)		55,632
Total Non-current	97,713		10		(115)		97,608
Total marketable securities	$	542,996	$	321	$	(216)	$	543,101