Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2012

Fair Value Measurements [Abstract]

Valuation of the company's assets measured at fair value

	Level 1		Level 2			Level 3		Total
	(In thousands)
As of June 30, 2012
Money market funds	$	106,329	$	—		$	—	$	106,329
Securities available-for-sale:
U.S. government obligations		—		41,501			—		41,501
Municipal securities		—		15,072			—		15,072
Corporate bonds		—		2,019			—		2,019
Foreign currency forward position		—		(181	)		—		(181	)
	$	106,329	$	58,411		$	—	$	164,740
As of December 31, 2011
Money market funds	$	111,256	$	—		$	—	$	111,256
Securities available-for-sale:
U.S. government obligations		—		55,460			—		55,460
Municipal securities		—		20,612			—		20,612
Corporate bonds		—		2,038			—		2,038
Foreign currency forward position		—		155			—		155
	$	111,256	$	78,265		$	—	$	189,521

Summary of the foreign currency forward contract

	As of
	June 30, 2012			December 31, 2011
	(In thousands)
Notional value	$	28,353		$	28,671
Fair value of notional		28,534			28,516
Gross and net fair value (liability) asset	$	(181	)	$	155

Summary of the company's securities available-for-sale

			Gross		Gross			Estimated
	Amortized		unrealized		unrealized			fair
	cost		gains		losses			value
	(In thousands)
As of June 30, 2012
U.S. government obligations	$	40,294	$	1,207	$	—		$	41,501
Municipal securities		15,070		5		(3	)		15,072
Corporate bonds		2,014		5		—			2,019
Total securities available-for-sale	$	57,378	$	1,217	$	(3	)	$	58,592
As of December 31, 2011
U.S. government obligations	$	53,832	$	1,628	$	—		$	55,460
Municipal securities		20,613		7		(8	)		20,612
Corporate bonds		2,028		10		—			2,038
Total securities available-for-sale	$	76,473	$	1,645	$	(8	)	$	78,110

Summary of contractual maturities of securities available-for-sale

	As of
	June 30, 2012		December 31, 2011
	(In thousands)
Less than one year	$	12,499	$	31,554
Due in 1—5 years		46,093		46,556
Total securities available-for-sale	$	58,592	$	78,110

Fair values and unrealized losses on securities available-for-sale

	Less than Twelve Months					Twelve Months or More				Total
	Estimated fair value		Gross unrealized losses			Estimated fair value		Gross unrealized losses		Estimated fair value		Gross unrealized losses
	(In thousands)
As of June 30, 2012
U.S. government obligations	$	—	$	—		$	—	$	—	$	—	$	—
Municipal securities		6,949		(3	)		—		—		6,949		(3	)
Corporate bonds		—		—			—		—		—		—
Total securities available-for-sale	$	6,949	$	(3	)	$	—	$	—	$	6,949	$	(3	)
As of December 31, 2011
U.S. government obligations	$	—	$	—		$	—	$	—	$	—	$	—
Municipal securities		9,529		(8	)		—		—		9,529		(8	)
Corporate bonds		—		—			—		—		—		—
Total securities available-for-sale	$	9,529	$	(8	)	$	—	$	—	$	9,529	$	(8	)