Investments (Tables)

3 Months Ended

Mar. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Summary of short-term investments

A summary of the Company’s short-term investments at March 31, 2013 and December 31, 2012 is as follows (in thousands):

	As of March 31, 2013								As of December 31, 2012
	Cost		Gross Gains		Gross Losses		Fair Value		Cost		Gross Gains		Gross Losses			Fair Value
Municipal Securities	$	12,384	$	15	$	—	$	12,399	$	12,520	$	—	$	(116	)	$	12,404
Corporate Debt Securities	28,855		25		—		28,880		26,575		—		(139		)	26,436
Commercial Paper	14,931		4		—		14,935		18,464		—		(2		)	18,462
Certificates of Deposits	—		—		—		—		19,047		—		—			19,047
Total	$	56,170	$	44	$	—	$	56,214	$	76,606	$	—	$	(257	)	$	76,349

Schedule of financial assets measured at fair value on a recurring basis

Financial assets measured at fair value on a recurring basis as of March 31, 2013 were as follows (in thousands):

	Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2		Significant Unobservable Inputs Level 3		Total
Money Market Funds (1)	$	31,265	$	—	$	—	$	31,265
Certificates of Deposits (2)	—		—		—		—
Corporate Debt Securities (2)	—		28,880		—		28,880
Commercial Paper (2)	—		14,935		—		14,935
Municipal Securities (2)	—		12,399		—		12,399
Auction rate notes (3)	—		—		4,241		4,241
Total	$	31,265	$	56,214	$	4,241	$	91,720

Financial assets measured at fair value on a recurring basis as of December 31, 2012 were as follows (in thousands):

	Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2		Significant Unobservable Inputs Level 3		Total
Money Market Funds (1)	$	13,845	$	—	$	—	$	13,845
Certificates of Deposits (2)	19,047		—		—		19,047
Corporate Debt Securities (2)	—		26,437		—		26,437
Commercial Paper (2)	—		18,462		—		18,462
Municipal Securities (2)	—		12,404		—		12,404
Auction rate notes (3)	—		—		4,159		4,159
Total	$	32,892	$	57,303	$	4,159	$	94,354

__________

(1) Included in cash and cash equivalents

(2) Included in short-term investments

(3) Included in long-term investments

Schedule of changes in Level 3 securities

For the three months ended March 31, 2013, the changes in the Company’s Level 3 securities (consisting of auction rate notes) were as follows (in thousands):

	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
Beginning balance, December 31, 2012	$	4,159
Transfers in and/or out of Level 3	—
Total unrealized gains, before tax	82
Settlements	—
Ending balance, March 31, 2013	$	4,241