Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Assets Measured at Fair Value

Assets and liabilities measured at fair value at each balance sheet date are as follows (in thousands):

	March 31, 2020
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	92,160	$	—	$	—	$	92,160
U.S. government treasuries	84,996		—		—		84,996
Commercial paper	—		2,996		—		2,996
Short-term marketable securities:
U.S. government treasuries	273,680		—		—		273,680
Corporate debt securities	—		61,766		—		61,766
Commercial paper	—		44,267		—		44,267
Long-term marketable securities:
U.S. government treasuries	2,565		—		—		2,565
Corporate debt securities	—		7,119		—		7,119
Total	$	453,401	$	116,148	$	—	$	569,549
Liabilities:
Foreign currency derivative contracts	$	—	$	141	$	—	$	141
Total	$	—	$	141	$	—	$	141

	December 31, 2019
	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	54,163	$	—	$	—	$	54,163
U.S. government treasuries	15,989		—		—		15,989
Short-term marketable securities:
U.S. government treasuries	250,070		—		—		250,070
U.S. government agency securities	—		2,000		—		2,000
Corporate debt securities	—		53,479		—		53,479
Commercial paper	—		30,358		—		30,358
Long-term marketable securities:
U.S. government treasuries	13,869		—		—		13,869
Corporate debt securities	—		26,017		—		26,017
Foreign currency derivative contracts	—		85		—		85
Total	$	334,091	$	111,939	$	—	$	446,030
Liabilities:
Foreign currency derivative contracts	$	—	$	8	$	—	$	8
Total	$	—	$	8	$	—	$	8