Cash Equivalents and Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2019

Investments, Debt and Equity Securities [Abstract]

Schedule of Marketable Securities

At June 30, 2019, marketable securities consisted of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Fair Value
Money market funds	$	71,937	$	—	$	—	$	71,937
U.S. treasury debt securities	3,931		5		—		3,936
U.S. corporate debt securities	38,833		97		(11)		38,919
	$	114,701	$	102	$	(11)	$	114,792
Included in cash and cash equivalents	$	71,937	$	—	$	—	$	71,937
Included in marketable securities	$	42,764	$	102	$	(11)	$	42,855

At December 31, 2018, marketable securities consisted of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Fair Value
Money market funds	$	52,068	$	—	$	—	$	52,068
Commercial paper	7,448		—		—		7,448
U.S. treasury debt securities	2,494		—		(1)		2,493
U.S. corporate debt securities	10,890		—		(67)		10,823
	$	72,900	$	—	$	(68)	$	72,832
Included in cash and cash equivalents	$	52,068	$	—	$	—	$	52,068
Included in marketable securities	$	20,832	$	—	$	(68)	$	20,764

Schedule of Cash and Cash Equivalents

At June 30, 2019, marketable securities consisted of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Fair Value
Money market funds	$	71,937	$	—	$	—	$	71,937
U.S. treasury debt securities	3,931		5		—		3,936
U.S. corporate debt securities	38,833		97		(11)		38,919
	$	114,701	$	102	$	(11)	$	114,792
Included in cash and cash equivalents	$	71,937	$	—	$	—	$	71,937
Included in marketable securities	$	42,764	$	102	$	(11)	$	42,855

At December 31, 2018, marketable securities consisted of the following (in thousands):

	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Fair Value
Money market funds	$	52,068	$	—	$	—	$	52,068
Commercial paper	7,448		—		—		7,448
U.S. treasury debt securities	2,494		—		(1)		2,493
U.S. corporate debt securities	10,890		—		(67)		10,823
	$	72,900	$	—	$	(68)	$	72,832
Included in cash and cash equivalents	$	52,068	$	—	$	—	$	52,068
Included in marketable securities	$	20,832	$	—	$	(68)	$	20,764

Schedule of Available-for-sale Securities, Continuous Unrealized Loss Position

The following table presents gross unrealized losses and fair values for those marketable securities that were in an unrealized loss position as of June 30, 2019, aggregated by investment category and the length of time that individual securities have been in a continuous loss position (in thousands):

	As of June 30, 2019
	Less than 12 months				12 months or greater
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U.S. treasury debt securities	$	—	$	—	$	—	$	—
U.S. corporate debt securities	996		(1)		3,494		(10)
Total	$	996	$	(1)	$	3,494	$	(10)