Fair Value Of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Summary of Assets and Liabilities Measured at Fair Value

Assets and liabilities measured at fair value on a recurring basis included the following as of June 30, 2019 and December 31, 2018 (in thousands):

	June 30, 2019								December 31, 2018
	Fair Value		Level 1		Level 2		Level 3		Fair Value		Level 1		Level 2		Level 3
Cash equivalents	$	312,857	$	312,857	$	—	$	—	$	129,172	$	129,172	$	—	$	—
Corporate bonds	7,998		—		7,998		—		58,033		—		58,033		—
U.S. treasury securities	—		—		—		—		138,726		—		138,726		—
Commercial paper	—		—		—		—		7,973		—		7,973		—
Total	$	320,855	$	312,857	$	7,998	$	—	$	333,904	$	129,172	$	204,732	$	—