Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2011

Fair Value Measurements

Schedule Of Fair Values Of Financial Instruments Measured On Recurring Basis

September 30, 2011	Level 1		Level 2		Level 3		Fair Value
Cash	$	134,190	$	—	$	—	$	134,190
Equity securities		2		—		—		2
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		5,563		—		—		5,563
Debt securities issued by states of the United States and political subdivisions of the states		14,027		—		—		14,027
Debt securities issued by foreign governments		3,552		—		—		3,552
Corporate debt securities		27,898		—		—		27,898
Auction rate securities		—		—		598		598
Total	$	185,232	$	—	$	598	$	185,830
December 31, 2010	Level 1		Level 2		Level 3		Fair Value
Cash	$	64,752	$	—	$	—	$	64,752
Equity securities		6		—		—		6
Debt securities issued by the U.S. Treasury and other U.S. government corporations and agencies		6,603		—		—		6,603
Debt securities issued by foreign governments		2,865		—		—		2,865
Corporate debt securities		12,240		—		—		12,240
Auction rate securities		—		—		496		496
Total	$	86,466	$	—	$	496	$	86,962

Schedule Of Changes In Fair Value Of Level 3 Financial Assets

	Level 3 Financial Assets
	Three Months Ended September 30, 2011		Nine Months Ended September 30, 2011
Beginning Balance	$	538	$	496
Total gains (losses) - realized/unrealized
Included in earnings		—		—
Not included in earnings		60		102
Purchases, issuances and settlements		—		—
Transfers in and/or out of Level 3		—		—
Balance, September 30, 2011	$	598	$	598
Total losses for the period included in earnings relating to assets still held at September 30, 2011	$	—	$	—