Short-Term Investments (Tables)

6 Months Ended

Jun. 30, 2014

Investments, Debt and Equity Securities [Abstract]

Summary of short-term investments

The following is a summary of short-term investments held as of June 30, 2014:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
Corporate debt	$	126,003	$	84	$	(55	)	$	126,032
U.S. government and agency debt	32,570		9		(3		)	32,576
Other fixed income securities	23,096		—		(7		)	23,089
Municipal bonds	21,625		11		—			21,636
Total short-term investments	$	203,294	$	104	$	(65	)	$	203,333

Schedule of contractual maturities of short-term investments

Contractual maturities of short-term investments as of June 30, 2014 are shown below. 

	Under 1 Year		1 to 5 Years		Total
	(in thousands)
Corporate debt	$	49,698	$	76,334	$	126,032
U.S. government and agency debt	24,515		8,061		32,576
Other fixed income securities	21,986		1,103		23,089
Municipal bonds	11,485		10,151		21,636
Total short-term investments	$	107,684	$	95,649	$	203,333