Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Investments Classified as Available-For-Sale

Marketable securities classified as available-for-sale as of June 30, 2018 and December 31, 2017 were comprised of (in thousands):

	June 30, 2018									December 31, 2017
	Amortized ‎Cost		Gross  ‎Unrealized  ‎Gains		Gross  ‎Unrealized  ‎Losses			Fair Value		Amortized ‎Cost		Gross  ‎Unrealized  ‎Gains		Gross  ‎Unrealized  ‎Losses			Fair Value
Asset-backed securities	$	—	$	—	$	—		$	—	$	13,748	$	—	$	(5	)	$	13,743
Corporate debt securities		78,631		10		(5	)		78,636		37,265		—		(12	)		37,253
Total	$	78,631	$	10	$	(5	)	$	78,636	$	51,013	$	—	$	(17	)	$	50,996