Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2017

Available-for-sale Securities [Abstract]

Cash equivalents and marketable securities classified as available-for-sale

All cash equivalents and marketable securities are classified as available-for-sale. Total cash, cash equivalents and marketable securities are summarized as follows:



	As of June 30, 2017
(In thousands)	Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Weighted Rate of Return
Money market funds	$	15,460	$	15,460	$	—	$	—		0.83	%
U.S. Government bonds and notes	63,612		63,610		2		—			0.83	%
Corporate notes, bonds, commercial paper and other	37,754		37,758		—		(4		)	0.97	%
Total cash equivalents and marketable securities	116,826		116,828		2		(4		)
Cash	51,127		51,127		—		—
Total cash, cash equivalents and marketable securities	$	167,953	$	167,955	$	2	$	(4	)



	As of December 31, 2016
(In thousands)	Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Weighted Rate of Return
Money market funds	$	10,681	$	10,681	$	—	$	—		0.41	%
U.S. Government bonds and notes	48,292		48,291		1		—			0.39	%
Corporate notes, bonds, commercial paper and other	62,178		62,199		—		(21		)	0.66	%
Total cash equivalents and marketable securities	121,151		121,171		1		(21		)
Cash	51,031		51,031		—		—
Total cash, cash equivalents and marketable securities	$	172,182	$	172,202	$	1	$	(21	)

Available-for-sale securities reported at fair value

Available-for-sale securities are reported at fair value on the balance sheets and classified as follows:



	As of
	June 30, 2017		December 31, 2016
	(In thousands)
Cash equivalents	$	116,080	$	84,263
Short term marketable securities	746		36,888
Total cash equivalents and marketable securities	116,826		121,151
Cash	51,127		51,031
Total cash, cash equivalents and marketable securities	$	167,953	$	172,182

Estimated fair value of cash equivalents and marketable securities classified by the length of time that the securities have been in a continuous unrealized loss position

The estimated fair value of cash equivalents and marketable securities classified by the length of time that the securities have been in a continuous unrealized loss position at June 30, 2017 and December 31, 2016 are as follows:



	Fair Value				Gross Unrealized Loss
	June 30, 2017		December 31, 2016		June 30, 2017			December 31, 2016
	(In thousands)
Less than one year
U.S. Government bonds and notes	$	8,997	$	18,395	$	—		$	—
Corporate notes, bonds and commercial paper	33,668		54,377		(4		)	(21		)
Total Corporate notes, bonds, and commercial paper and U.S. Government bonds and notes	$	42,665	$	72,772	$	(4	)	$	(21	)