Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value, Assets Measured on Recurring and Nonrecurring Basis

The following tables set forth the amortized cost, gross unrealized gains, gross unrealized losses and fair values of the Company’s marketable securities accounted for as available-for-sale securities as of June 30, 2021 and December 31, 2020.

	June 30, 2021
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Financial Assets:
Short-term marketable securities:
U.S. Treasury securities	$	51,637	$	1	$	(78)	$	51,560
Yankee bonds	3,075		—		(6)		3,069
Agency bonds	17,641		—		(6)		17,635
Municipal bonds	12,515		—		(43)		12,472
Commercial paper	22,658		—		—		22,658
Asset-backed securities	26,493		1		(27)		26,467
Corporate bonds	69,315		—		(226)		69,089
Total	$	203,334	$	2	$	(386)	$	202,950

	December 31, 2020
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Financial Assets:
Short-term marketable securities:
U.S. Treasury securities	$	21,357	$	1	$	(18)	$	21,340
Commercial paper	14,543		—		—		14,543
Asset-backed securities	14,546		—		(8)		14,538
Corporate bonds	17,144		—		(19)		17,125
Total	$	67,590	$	1	$	(45)	$	67,546

Investments Classified by Contractual Maturity Date

The following tables set forth the fair value of available-for-sale marketable securities by contractual maturity at June 30, 2021 and December 31, 2020.

	June 30, 2021
(in thousands)	One Year or Less		Over One Year Through Five Years		Over Five Years		Total
Financial Assets:
Marketable Securities:
U.S. Treasury securities	$	13,593	$	37,967	$	—	$	51,560
Yankee bonds	—		3,069		—		3,069
Agency bonds	10,587		7,048		—		17,635
Municipal bonds	—		12,472		—		12,472
Commercial paper	22,658		—		—		22,658
Asset-backed securities	—		26,467		—		26,467
Corporate bonds	24,066		45,023		—		69,089
Total	$	70,904	$	132,046	$	—	$	202,950

	December 31, 2020
(in thousands)	One Year or Less		Over One Year Through Five Years		Over Five Years		Total
Financial Assets:
Marketable Securities:
U.S. Treasury securities	$	6,075	$	15,265	$	—	$	21,340
Commercial paper	14,543		—		—		14,543
Asset-backed securities	560		13,978		—		14,538
Corporate bonds	5,863		11,262		—		17,125
Total	$	27,041	$	40,505	$	—	$	67,546

Fair Value, Assets Measured on Recurring Basis

The following tables set forth the Company’s cash equivalents and marketable securities accounted for as available-for-sale securities that were measured at fair value on a recurring basis based on the fair value hierarchy as of June 30, 2021 and December 31, 2020.

	June 30, 2021
(in thousands)	Level 1		Level 2		Level 3		Total
Financial Assets:
Cash equivalents:
Money market funds	$	263,880	$	—	$	—	$	263,880
Commercial paper	—		17,546		—		17,546
Marketable securities:
U.S. Treasury securities	51,560		—		—		51,560
Yankee bonds	3,069		—		—		3,069
Agency bonds	17,635		—		—		17,635
Municipal bonds	12,472		—		—		12,472
Commercial paper	—		22,658		—		22,658
Asset-backed securities	—		26,467		—		26,467
Corporate bonds	—		69,089		—		69,089
Total	$	348,616	$	135,760	$	—	$	484,376

	December 31, 2020
(in thousands)	Level 1			Level 2		Level 3		Total
Financial Assets:
Cash equivalents:
Money market funds	$	209,141		$	—	$	—	$	209,141
U.S. Treasury securities	1,000			—		—		1,000
Commercial paper	—			3,999		—		3,999
Marketable securities:
U.S. Treasury securities	21,340			—		—		21,340
Commercial paper	—			14,543		—		14,543
Asset-backed securities	—			14,538		—		14,538
Corporate bonds	—		—	17,125		—		17,125
Total	$	231,481		$	50,205	$	—	$	281,686