Financial Instruments

Cash, Cash Equivalents and Marketable Securities

The following tables summarize our cash and available-for-sale securities by significant investment category.



	September 27, 2013
(In thousands)	Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents		Short-Term Marketable Securities		Long-Term Marketable Securities

Cash	$	55,645	$	—	$	—		$	55,645	$	55,645	$	—	$	—

Available-for-sale:
Level 1:
Money market funds	2,875,377		—		—			2,875,377		2,875,377		—		—
U.S. treasury securities	595,841		18		(1,369		)	594,490		22,525		50,248		521,717
Subtotal	3,471,218		18		(1,369		)	3,469,867		2,897,902		50,248		521,717

Level 2:
U.S. agency securities	59,850		35		(27		)	59,858		2,538		14,272		43,048
Non-U.S. government securities	17,389		5		(1		)	17,393		—		9,338		8,055
Municipal bond	1,606		—		(6		)	1,600		—		606		994
Corporate securities	216,277		371		(116		)	216,532		—		76,695		139,837
Subtotal	295,122		411		(150		)	295,383		2,538		100,911		191,934
Total	$	3,821,985	$	429	$	(1,519	)	$	3,820,895	$	2,956,085	$	151,159	$	713,651



	December 31, 2012
(In thousands)	Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents		Short-Term Marketable Securities		Long-Term Marketable Securities

Cash	$	89,194	$	—	$	—		$	89,194	$	89,194	$	—	$	—

Available-for-sale:
Level 1:
Money market funds	2,739,904		—		—			2,739,904		2,739,904		—		—
U.S. treasury securities	564,713		5,231		(3		)	569,941		33,519		22,493		513,929
Subtotal	3,304,617		5,231		(3		)	3,309,845		2,773,423		22,493		513,929

Level 2:
U.S. agency securities	116,802		58		(1		)	116,859		11,799		53,438		51,622
Non-U.S. government securities	11,644		10		(2		)	11,652		—		2,730		8,922
Municipal bond	1,372		1		—			1,373		—		752		621
Corporate securities	193,048		436		(64		)	193,420		2,211		61,545		129,664
Subtotal	322,866		505		(67		)	323,304		14,010		118,465		190,829
Total	$	3,716,677	$	5,736	$	(70	)	$	3,722,343	$	2,876,627	$	140,958	$	704,758

We have certain cost method investments of approximately $7.0 million. These investments are included within Other assets, net in our consolidated balance sheets.

The adjusted cost and estimated fair value of marketable debt securities (corporate securities, municipal bonds, U.S. and foreign government securities, and U.S. treasury securities) as of September 27, 2013, by contractual maturity, are shown below. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations without call or prepayment penalties.



	September 27, 2013
(In thousands)	Cost		Estimated Fair Value
Due in one year or less	$	176,134	$	176,222
Due after one year through five years	714,829		713,651
	$	890,963	$	889,873

As of September 27, 2013, $609.7 million of our total available-for-sale securities has been in a continuous unrealized loss position for less than 12 months with a gross unrealized loss of $1.5 million. As of December 31, 2012, $118.7 million of the total available-for-sale securities was in a continuous loss position for less than 12 months with a gross unrealized loss of $0.1 million.