Cash Equivalents and Investments (Tables)

12 Months Ended

Dec. 31, 2014

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		Fair Value		Cash and Cash Equivalents		Short-Term Investments
(In thousands)
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
December 31, 2013
Cash	$	8,332	$	—	$	—	$	8,332	$	8,332	$	—
Money market funds	85,970		—		—		85,970		85,970		—
Corporate securities	3,500		1,738		—		5,238		—		5,238
Total	$	97,802	$	1,738	$	—	$	99,540	$	94,302	$	5,238