Investments (Tables)

6 Months Ended

Jun. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule of Available-for-Sale Investments

The following tables summarize the Company’s available-for-sale investments at June 30, 2018 and December 31, 2017 (in thousands):

	June 30, 2018
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Certificates of deposit	$	13,682	$	—	$	—		$	13,682
U.S. Treasury securities	31,850		1		(107		)	31,744
U.S. Agency securities	7,013		—		(69		)	6,944
Commercial paper	35,917		—		—			35,917
Asset-backed securities	8,992		2		(1		)	8,993
Corporate notes and bonds	33,388		1		(75		)	33,314
Total	$	130,842	$	4	$	(252	)	$	130,594

	December 31, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Certificates of deposit	$	13,441	$	—	$	—		$	13,441
U.S. Treasury securities	14,787		—		(71		)	14,716
U.S. Agency securities	8,510		—		(51		)	8,459
Commercial paper	9,171		—		—			9,171
Asset-backed securities	3,026		—		(1		)	3,025
Corporate notes and bonds	31,906		—		(70		)	31,836
Total	$	80,841	$	—	$	(193	)	$	80,648

Schedule of Available-For-Sale Investment Maturities

The following table summarizes the maturities of the Company’s available-for-sale securities at June 30, 2018 and December 31, 2017 (in thousands):

	June 30, 2018				December 31, 2017
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due in less than 1 year	$	95,448	$	95,312	$	55,801	$	55,735
Due in 1-5 years	35,394		35,282		25,040		24,913
Total	$	130,842	$	130,594	$	80,841	$	80,648