MARKETABLE SECURITIES

9 Months Ended

Sep. 30, 2011

MARKETABLE SECURITIES

MARKETABLE SECURITIES

NOTE 6—MARKETABLE SECURITIES

        At September 30, 2011, available-for-sale marketable securities are as follows (in thousands):

			Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Corporate debt securities			$	67,833	$	116	$	(41	)	$	67,908
States of the U.S. and state political subdivisions				111,604		603		(66	)		112,141
	Total debt securities			179,437		719		(107	)		180,049
	Equity security			5,735		—		(103	)		5,632
		Total marketable securities	$	185,172	$	719	$	(210	)	$	185,681

        At December 31, 2010, available-for-sale marketable securities are as follows (in thousands):

			Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Corporate debt securities			$	237,406	$	773	$	(16	)	$	238,163
States of the U.S. and state political subdivisions				110,478		373		(230	)		110,621
U.S. Treasury securities				199,881		18		—			199,899
	Total debt securities			547,765		1,164		(246	)		548,683
	Equity security			12,896		2,418		—			15,314
		Total marketable securities	$	560,661	$	3,582	$	(246	)	$	563,997

        The net unrealized gains in the tables above are included in "Accumulated other comprehensive income" in the accompanying consolidated balance sheet.

        The contractual maturities of debt securities classified as available-for-sale at September 30, 2011 are as follows (in thousands):

		Amortized Cost		Estimated Fair Value
Due in one year or less		$	98,145	$	98,410
Due after one year through five years			81,292		81,639
	Total	$	179,437	$	180,049

        The following table summarizes investments in marketable debt securities (16 in total at September 30, 2011) that have been in a continuous unrealized loss position for less than twelve months (in thousands):

		September 30, 2011					December 31, 2010
		Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Corporate debt securities		$	16,995	$	(41	)	$	34,552	$	(16	)
States of the U.S. and state political subdivisions			26,224		(66	)		39,171		(230	)
	Total	$	43,219	$	(107	)	$	73,723	$	(246	)

        At September 30, 2011 and December 31, 2010, there are no investments in marketable securities that have been in a continuous unrealized loss position for twelve months or longer.

        Substantially all of the Company's marketable debt securities are rated investment grade. The gross unrealized losses on the marketable debt securities relate to changes in interest rates. Because the Company does not intend to sell any marketable debt securities and it is not more likely than not that the Company will be required to sell any marketable debt securities before recovery of their amortized cost bases, which may be maturity, the Company does not consider any of its marketable debt securities to be other-than-temporarily impaired at September 30, 2011. The gross unrealized loss on the marketable equity security is not considered other-than-temporarily impaired at September 30, 2011 because of the short duration and lack of severity of the loss.

        The following table presents the proceeds from maturities and sales of available-for-sale marketable securities and the related gross realized gains and losses (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2011		2010		2011			2010
	(In thousands)
Proceeds from maturities and sales of available-for-sale marketable securities	$	128,287	$	240,584	$	542,191		$	612,452
Gross realized gains		387		328		2,303			4,660
Gross realized losses		—		—		(18	)		(7	)

        Gross realized gains and losses from the maturities and sales of marketable securities and from the sales of investments are included in "Other income, net" in the accompanying consolidated statement of operations.