Cash Equivalents and Investments (Tables)

3 Months Ended

Mar. 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		Estimated Fair Value		Cash and Cash Equivalents		Short-Term Investments
(In thousands)
March 31, 2014
Cash	$	168,984	$	—	$	—	$	168,984	$	168,984	$	—
Money market funds	165,051		—		—		165,051		165,051		—
Corporate securities	3,500		58		—		3,558		—		3,558
Total	$	337,535	$	58	$	—	$	337,593	$	334,035	$	3,558
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