Cash, Cash Equivalents and Investments (Tables)

12 Months Ended

Dec. 31, 2020

Cash and Cash Equivalents [Abstract]

Summary of Cash, Cash Equivalents and Held-to-Maturity Investments by Type

The following tables summarize the Company’s cash, cash equivalents, and held-to-maturity investments at December 31, 2020 and December 31, 2019 (in thousands):

	As of December 31, 2020
			Gross		Gross				Cash and
	Amortized		Unrealized		Unrealized				Cash		Short-Term		Long-Term
	Cost		Gains		Losses		Fair Value		Equivalents		Investments		Investments
Cash	$	116,107	$	—	$	—	$	116,107	$	116,107	$	—	$	—
Level 1:
Money market funds		23,611		—		—		23,611		23,611		—		—
Agency bonds		63,794		122		—		63,916		—		23,794		40,000
Treasury bills		96,384		6		—		96,390		—		96,384		—
Subtotal		183,789		128		—		183,917		23,611		120,178		40,000
Level 2:
State and municipal obligations		77,130		25		(28)		77,127		—		66,519		10,611
Certificates of deposit		500		—		—		500		—		500		—
Corporate bonds		212,825		232		(100)		212,957		2,525		170,205		40,095
U.S. Treasury repurchase agreements		13,200		—		—		13,200		13,200		—		—
Treasury inflation-protected securities		3,291		16		—		3,307		—		3,291		—
Commercial paper		45,974		—		—		45,974		—		45,974		—
Subtotal		352,920		273		(128)		353,065		15,725		286,489		50,706
Total	$	652,816	$	401	$	(128)	$	653,089	$	155,443	$	406,667	$	90,706

	As of December 31, 2019
			Gross		Gross				Cash and
	Amortized		Unrealized		Unrealized				Cash		Short-Term		Long-Term
	Cost		Gains		Losses		Fair Value		Equivalents		Investments		Investments
Cash	$	103,319	$	—	$	—	$	103,319	$	103,319	$	—	$	—
Level 1:
Money market funds		8,845		—		—		8,845		8,845		—		—
Agency bonds		32,869		14		(4)		32,879		—		15,131		17,738
Subtotal		41,714		14		(4)		41,724		8,845		15,131		17,738
Level 2:
State and municipal obligations		25,038		8		—		25,046		—		21,560		3,478
Certificates of deposit		1,400		—		—		1,400		—		1,400		—
Corporate bonds		135,175		71		(30)		135,216		886		113,241		21,048
U.S. Treasury repurchase agreements		57,200		—		—		57,200		57,200		—		—
Treasury inflation-protected securities		3,235		14		—		3,249		—		—		3,235
Commercial paper		29,202		—		—		29,202		2,000		27,202		—
Subtotal		251,250		93		(30)		251,313		60,086		163,403		27,761
Total	$	396,283	$	107	$	(34)	$	396,356	$	172,250	$	178,534	$	45,499