Investments (Tables)

12 Months Ended

Dec. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Schedule of Short-Term Investments

The following tables summarize the Company's short-term investments (in thousands):

		As of December 31, 2019
	Maturity	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
Corporate debt securities	2 years or less	$	160,065	$	233	$	(1	)	$	160,297
Commercial paper	1 year or less	120,862		74		—			120,936
U.S. Agency Bonds	2 years or less	50,745		41		(4		)	50,782
U.S. Treasury bills	2 years or less	36,474		27		(1		)	36,500
		$	368,146	$	375	$	(6	)	$	368,515

		As of December 31, 2018
	Maturity	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
Corporate debt securities	1 year or less	$	111,933	$	26	$	(43	)	$	111,916
Commercial paper	1 year or less	74,433		—		(24		)	74,409
U.S. Treasury bills	1 year or less	3,771		—		—			3,771
		$	190,137	$	26	$	(67	)	$	190,096