Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2012

Fair Value Measurements [Abstract]

Valuation of the company's assets and liabilities measured at fair value

	Level 1		Level 2			Level 3		Total
	(In thousands)
As of September 30, 2012
Money market funds	$	125,474	$	—		$	—	$	125,474
Securities available-for-sale:
U.S. government obligations		—		41,376			—		41,376
Municipal securities		—		10,784			—		10,784
Corporate bonds		—		2,021			—		2,021
Foreign currency forward position		—		(47	)		—		(47	)
	$	125,474	$	54,134		$	—	$	179,608
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
	September 30, 2012			December 31, 2011
	(In thousands)
Notional value	$	13,346		$	28,671
Fair value of notional		13,393			28,516
Gross and net fair value (liability) asset	$	(47	)	$	155

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

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
	(In thousands)
As of September 30, 2012
U.S. government obligations	$	40,256	$	1,120	$	—		$	41,376
Municipal securities		10,778		7		(1	)		10,784
Corporate bonds		2,018		3		—			2,021
Total securities available-for-sale	$	53,052	$	1,130	$	(1	)	$	54,181
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
	September 30, 2012		December 31, 2011
	(In thousands)
Less than one year	$	11,272	$	31,554
Due in 1 - 5 years		42,909		46,556
Total securities available-for-sale	$	54,181	$	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 September 30, 2012
U.S. government obligations	$	—	$	—		$	—	$	—	$	—	$	—
Municipal securities		2,108		(1	)		—		—		2,108		(1	)
Corporate bonds		—		—			—		—		—		—
Total securities available-for-sale	$	2,108	$	(1	)	$	—	$	—	$	2,108	$	(1	)
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	)