Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Measurements [Abstract]

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

	Level 1		Level 2			Level 3		Total
	(In thousands)
As of March 31, 2013
Money market funds	$	99,801	$	—		$	—	$	99,801
Securities available-for-sale:
U.S. government obligations		—		—			—		—
Municipal securities		—		14,934			—		14,934
Corporate bonds		—		2,125			—		2,125
Foreign currency forward position		—		(251	)		—		(251	)
	$	99,801	$	16,808		$	—	$	116,609
As of December 31, 2012
Money market funds	$	83,519	$	—		$	—	$	83,519
Securities available-for-sale
U.S. government obligations		—		31,104			—		31,104
Municipal securities		—		17,947			—		17,947
Corporate bonds		—		2,157			—		2,157
Foreign currency forward and option contracts		—		15			—		15
	$	83,519	$	51,223		$	—	$	134,742

Summary of foreign currency forward contract

	As of
	March 31, 2013			December 31, 2012
	(In thousands)
Notional value	$	26,235		$	15,792
Fair value of notional		26,486			15,809
Gross and net fair value (liability)	$	(251	)	$	(17	)

Summary of company's securities available-for-sale

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
	(In thousands)
As of March 31, 2013
U.S. government obligations	$	—	$	—	$	—		$	—
Municipal securities		14,915		19		—			14,934
Corporate bonds		2,115		10		—			2,125
Total securities available-for-sale	$	17,030	$	29	$	—		$	17,059
As of December 31, 2012
U.S. government obligations	$	30,255	$	849	$	—		$	31,104
Municipal securities		17,941		10		(4	)		17,947
Corporate bonds		2,159		—		(2	)		2,157
Total securities available-for-sale	$	50,355	$	859	$	(6	)	$	51,208

Summary of contractual maturities of securities available-for-sale

	As of
	March 31, 2013		December 31, 2012
	(In thousands)
Less than one year	$	9,695	$	10,870
Due in 1 – 5 years		7,364		40,338
Total securities available-for-sale	$	17,059	$	51,208

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

	Less than Twelve Months					Twelve Months or More				Total
	Estimated		Gross			Estimated		Gross		Estimated		Gross
	fair		unrealized			fair		unrealized		fair		unrealized
	value		losses			value		losses		value		losses
	(In thousands)
As of December 31, 2012
U.S. government obligations	$	—	$	—		$	—	$	—	$	—	$	—
Municipal securities		2,780		(4	)		—		—		2,780		(4	)
Corporate bonds		2,157		(2	)		—		—		2,157		(2	)
Total securities available-for-sale	$	4,937	$	(6	)	$	—	$	—	$	4,937	$	(6	)