Marketable Securities, Available-for-sale (Tables)

9 Months Ended

Sep. 30, 2011

Marketable Securities, Available-for-sale

Fair value of the available-for-sale marketable securities, by type of security

	SEPTEMBER 30, 2011
(in thousands)	AMORTIZED COST		GROSS UNREALIZED GAINS		GROSS UNREALIZED LOSSES			ESTIMATED FAIR VALUE
Type of security:
U.S. Treasury securities	$	2,903	$	-	$	-		$	2,903
Obligations of U.S. and local government agencies	86,129		31		(13		)	86,147
Corporate debt securities issued under
U.S. government/agency-backed programs	1,454		-		-			1,454
Corporate debt securities	136,936		107		(725		)	136,318
Asset-backed securities	71,468		67		(294		)	71,241
Total debt securities	298,890		205		(1,032		)	298,063
Time deposits	25,592		-		-			25,592
Short-term pooled investments	15,097		-		-			15,097
Total marketable securities, available-for-sale	$	339,579	$	205	$	(1,032	)	$	338,752
	DECEMBER 31, 2010
Type of security:
U.S. Treasury securities	$	15,782	$	81	$	-		$	15,863
Obligations of U.S. and local government agencies	33,247		12		(215		)	33,044
Corporate debt securities issued under
U.S. government/agency-backed programs	170,878		112		-			170,990
Corporate debt securities	104,976		218		(92		)	105,102
Asset-backed securities	7,643		1		(12		)	7,632
Total debt securities	332,526		424		(319		)	332,631
Time deposits	76,312		-		-			76,312
Short-term pooled investments	28,850		2		-			28,852
Total marketable securities, available-for-sale	$	437,688	$	426	$	(319	)	$	437,795

Fair value of the available-for-sale marketable securities, by contractual maturity

(in thousands)	SEPTEMBER 30, 2011		DECEMBER 31, 2010
Contractual maturity:
Maturing in one year or less	$	115,922	$	22,244
Maturing after one year through three years	133,394		299,381
Maturing after three years	48,747		11,006
Total debt securities	298,063		332,631
Time deposits and short-term pooled investments	40,689		105,164
Total marketable securities, available-for-sale	$	338,752	$	437,795