Fair Value Measurements

9 Months Ended

Sep. 30, 2011

Fair Value Measurements

Fair Value Measurements

Note 3.  Fair Value Measurements

The Company measures certain financial assets, including cash equivalents and marketable securities, at their fair value on a recurring basis. The fair value of these financial assets was determined based on a hierarchy of three levels of inputs, of which the first two are considered observable and the last unobservable, as follows:

Level 1:  Quoted prices in active markets for identical assets or liabilities.

Level 2:  Observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3:  Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. The Company did not have any non-financial assets or liabilities that were measured or disclosed at fair value on a recurring basis at September 30, 2011 and December 31, 2010, respectively. The following tables set forth the Company’s financial instruments that were measured at fair value on a recurring basis at September 30, 2011 and December 31, 2010 by level within the fair value hierarchy:

	Actively QuotedMarkets forIdentical AssetsLevel 1		Significant OtherObservableInputsLevel 2			SignificantUnobservableInputsLevel 3		Balance atSeptember 30,2011
	(In thousands)
As of September 30, 2011:
Assets
Money market deposits	$	13,359	$	—		$	—	$	13,359
U.S. Treasury securities	1,004		—			—		1,004
Debt securities of U.S. government-sponsored entities	—		9,493			—		9,493
Commercial paper	—		18,249		(1)	—		18,249		(1)
Corporate debt securities	—		23,663		(2)	—		23,663		(2)
Total	$	14,363	$	51,405		$	—	$	65,768

	Actively QuotedMarkets forIdentical AssetsLevel 1		Significant OtherObservableInputsLevel 2		SignificantUnobservableInputsLevel 3		Balance atDecember 31,2010
	(In thousands)
As of December 31, 2010:
Assets
Money market deposits	$	9,956	$	—	$	—	$	9,956
U.S. Treasury securities	3,818		—		—		3,818
Debt securities of U.S. government-sponsored entities	—		20,819		—		20,819
Commercial paper	—		11,869		—		11,869
Corporate debt securities	—		9,129		—		9,129
Total	$	13,774	$	41,817	$	—	$	55,591

(1)Includes commercial paper with a fair value of $3.0 million that matures within three months of September 30, 2011 and was classified as cash equivalents on the condensed consolidated balance sheet as of September 30, 2011.

(2)Includes a corporate bond with a fair value of $296,000 that matures within three months of September 30, 2011 and was classified as cash equivalents on the condensed consolidated balance sheet as of September 30, 2011.

The Company’s debt securities of U.S. government-sponsored entities, commercial paper and corporate bonds are classified as Level 2 as they are valued using multi-dimensional relational pricing models that use observable market inputs, including benchmark yields, reported trades, broker-dealer quotes, issuer spreads, benchmark securities, bids, offers and reference data. Not all inputs listed are available for use in the evaluation process on any given day for each security evaluation. In addition, market indicators, industry and economic events are monitored and may serve as a trigger to acquire further corroborating market data. There were no transfers between Level 1 and Level 2 categories during the three and nine months ended September 30, 2011 and 2010.

All of the Company’s marketable securities are classified as available-for-sale. The following tables illustrate the Company’s available-for-sale marketable securities as of the dates indicated:

	September 30, 2011
	AmortizedCost		UnrealizedGains		UnrealizedLosses			EstimatedFair Value
	(In thousands)
U.S. Treasury securities	$	1,004	$	—	$	—		$	1,004
Debt securities of U.S. government-sponsored entities	9,499		2		(8		)	9,493
Commercial paper	15,238		11		—			15,249
Corporate debt securities	23,414		—		(47		)	23,367
Total	$	49,155	$	13	$	(55	)	$	49,113

	December 31, 2010
	AmortizedCost		UnrealizedGains		UnrealizedLosses			EstimatedFair Value
	(In thousands)
U.S. Treasury securities	$	3,818	$	—	$	—		$	3,818
Debt securities of U.S. government-sponsored entities	20,825		1		(7		)	20,819
Commercial paper	11,868		2		(1		)	11,869
Corporate debt securities	9,134		—		(5		)	9,129
Total	$	45,645	$	3	$	(13	)	$	45,635

The Company had no realized gains or losses on available-for-sale marketable securities during the three and nine months ended September 30, 2011 and 2010, respectively.

The following table summarizes the Company’s portfolio of available-for-sale marketable securities by contractual maturity as of the dates indicated:

	September 30, 2011				December 31, 2010
	AmortizedCost		Estimated Fair Value		AmortizedCost		Estimated Fair Value
	(In thousands)
Due in one year or less	$	40,310	$	40,278	$	45,645	$	45,635
Due in more than one year but less than five years	8,845		8,835		—		—
Total	$	49,155	$	49,113	$	45,645	$	45,635