Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2020

Fair Value Disclosures [Abstract]

Valuation of Company's Assets and Liabilities Measured at Fair Value

The following table summarizes the valuation of the Company’s assets and liabilities measured at fair value as categorized based on the hierarchy described in Note 2.

	Level 1		Level 2			Level 3		Total
	(In thousands)
As of June 30, 2020
Money market funds	$	153,750	$	—		$	—	$	153,750
Securities available-for-sale
Corporate debt		—		102,151			—		102,151
Trading securities
Corporate debt		—		21,645			—		21,645
Mutual funds held in rabbi trust		—		7,576			—		7,576
Foreign currency forward position		—		1,396			—		1,396
Total	$	153,750	$	132,768		$	—	$	286,518
As of December 31, 2019
Money market funds	$	99,755	$	—		$	—	$	99,755
Securities available-for-sale
Corporate debt		—		137,835			—		137,835
Trading securities
Corporate debt		—		31,120			—		31,120
U.S. Treasuries		—		55,305			—		55,305
Mutual funds held in rabbi trust		—		6,217			—		6,217
Foreign currency forward position		—		(2,772	)		—		(2,772	)
Total	$	99,755	$	227,705		$	—	$	327,460

Summary of Foreign Currency Forward Contracts

A summary of the Company’s foreign currency forward position is as follows:

	As of
	June 30, 2020		December 31, 2019
	(In thousands)
Notional value	$	179,109	$	155,885
Fair value of notional		177,713		158,657
Fair value of the asset (liability)	$	1,396	$	(2,772	)

Summary of Company's Investments

The following is a summary of the Company’s investments:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
	(In thousands)
As of June 30, 2020
Securities available-for-sale
Corporate debt	$	101,001	$	1,167	$	(17	)	$	102,151
Trading securities
Corporate debt		21,556		90		(1	)		21,645
Mutual funds held in rabbi trust		7,680		54		(158	)		7,576
Total trading securities		29,236		144		(159	)		29,221
Total investments	$	130,237	$	1,311	$	(176	)	$	131,372
As of December 31, 2019
Securities available-for-sale
Corporate debt	$	137,119	$	721	$	(5	)	$	137,835
Trading securities
Corporate debt		31,120		14		(14	)		31,120
U.S. Treasuries		54,738		567		—			55,305
Mutual funds held in rabbi trust		5,173		1,044		—			6,217
Total trading securities		91,031		1,625		(14	)		92,642
Total investments	$	228,150	$	2,346	$	(19	)	$	230,477

Summary of Fair Value of Investments Based upon Contractual Maturities

The following table summarizes the fair value of the investments based upon the contractual maturities:

	As of
	June 30, 2020		December 31, 2019
	(In thousands)
Less than one year	$	77,068	$	120,850
Due in 1 - 5 years		54,304		109,627
Total	$	131,372	$	230,477

Fair Values and Unrealized Losses on Investments

The following table provides fair values and unrealized losses on investments and by the aging of the securities’ continuous unrealized loss position as of June 30, 2020 and December 31, 2019:

	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, 2020
Corporate debt	$	11,578	$	(18	)	$	—	$	—		$	11,578	$	(18	)
As of December 31, 2019
Corporate debt	$	27,999	$	(18	)	$	4,406	$	(1	)	$	32,405	$	(19	)