Cash Equivalents and Investments (Tables)

9 Months Ended

Sep. 30, 2015

Cash and Cash Equivalents [Abstract]

Summary of cash and available-for-sale securities

Summary of Cash and Available-For-Sale Securities	Adjusted Cost		Unrealized Gains		Unrealized Losses		Estimated Fair Value		Cash and Cash Equivalents		Short-Term Investments
(In thousands)
September 30, 2015
Cash	$	88,005	$	—	$	—	$	88,005	$	88,005	$	—
Money market funds	139,850		—		—		139,850		139,850		—
Corporate securities	1,206		621		—		1,827		—		1,827
Total	$	229,061	$	621	$	—	$	229,682	$	227,855	$	1,827
December 31, 2014
Cash	$	69,585	$	—	$	—	$	69,585	$	69,585	$	—
Money market funds	221,792		—		—		221,792		221,792		—
Corporate securities	1,750		560		—		2,310		—		2,310
Total	$	293,127	$	560	$	—	$	293,687	$	291,377	$	2,310