INVESTMENTS (Tables)

3 Months Ended

Mar. 31, 2016

INVESTMENTS

Schedule of investments

	Amortized		Gross Unrealized				Estimated
	Cost		Gains		Losses(1)		Fair Value
	(In thousands)
March 31, 2016
Short-term investments:
Available-for-sale securities:
U.S. government and agency debt securities	$	226,243	$	213	$	(25)	$	226,431
Corporate debt securities		163,918		150		(75)		163,993
International government agency debt securities		35,013		13		(36)		34,990
Total short-term investments		425,174		376		(136)		425,414
Long-term investments:
Available-for-sale securities:
U.S. government and agency debt securities		63,945		—		(40)		63,905
Corporate debt securities		26,778		—		(75)		26,703
		90,723		—		(115)		90,608
Held-to-maturity securities:
Fixed term deposit account		1,667		—		—		1,667
Certificates of deposit		1,715		—		—		1,715
		3,382		—		—		3,382
Total long-term investments		94,105		—		(115)		93,990
Total investments	$	519,279	$	376	$	(251)	$	519,404
December 31, 2015
Short-term investments:
Available-for-sale securities:
Corporate debt securities	$	175,098	$	20	$	(179)	$	174,939
U.S. government and agency debt securities		141,789		51		(104)		141,736
International government agency debt securities		37,070		—		(76)		36,994
Total short-term investments		353,957		71		(359)		353,669
Long-term investments:
Available-for-sale securities:
U.S. government and agency debt securities		211,216		—		(764)		210,452
Corporate debt securities		38,381		—		(111)		38,270
International government agency debt securities		12,039		—		(71)		11,968
		261,636		—		(946)		260,690
Held-to-maturity securities:
Fixed term deposit account		1,666		—		—		1,666
Certificates of deposit		1,715		—		—		1,715
		3,381		—		—		3,381
Total long-term investments		265,017		—		(946)		264,071
Total investments	$	618,974	$	71	$	(1,305)	$	617,740

(1) Losses represent marketable securities that were in loss positions for less than one year.

Proceeds from the sales and maturities of marketable securities, plus the resulting realized gains and losses

	Three Months Ended
	March 31,
(In thousands)	2016		2015
Proceeds from the sales and maturities of marketable securities	$	158,224	$	98,927
Realized gains	$	63	$	11
Realized losses	$	28	$	—

The cost and fair value of available-for-sale and held-to-maturity securities by contractual maturity

The Company’s available-for-sale and held-to-maturity securities at March 31, 2016 had contractual maturities in the following periods:

	Available-for-sale				Held-to-maturity
	Amortized		Estimated		Amortized		Estimated
(In thousands)	Cost		Fair Value		Cost		Fair Value
Within 1 year	$	255,325	$	255,260	$	1,715	$	1,715
After 1 year through 5 years		260,572		260,762		1,667		1,667
Total	$	515,897	$	516,022	$	3,382	$	3,382