Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Assets Measured on Recurring Basis

The following table summarizes the assets and liabilities measured at fair value on a recurring basis (in thousands):

	December 31, 2019
	Total		Level 1		Level 2
Assets
Cash and cash equivalents:
Cash	$	662	$	662	$	—
Money market funds	45,873		45,873		—
Total cash and cash equivalents	46,535		46,535		—
Short-term investments:
U.S. Treasury bills	36,500		36,500		—
Corporate debt securities	160,297		—		160,297
Commercial paper	120,936		—		120,936
U.S. Agency bonds	50,782		—		50,782
Total short-term investments	368,515		36,500		332,015
Total	$	415,050	$	83,035	$	332,015

	December 31, 2018
	Total		Level 1		Level 2
Assets
Cash and cash equivalents:
Cash	$	3,731	$	3,731	$	—
Money market funds	28,963		28,963		—
Total cash and cash equivalents	32,694		32,694		—
Short-term investments:
U.S. Treasury Bills	3,771		3,771		—
Corporate debt securities	111,916		—		111,916
Commercial paper	74,409		—		74,409
Total short-term investments	190,096		3,771		186,325
Total	$	222,790	$	36,465	$	186,325