Financial Instruments (Tables)

9 Months Ended

Sep. 26, 2014

Investments, Debt and Equity Securities [Abstract]

Schedule of Cash and Available-for-sale Securities by Significant Investment Category (Table Text Block)

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

	September 26, 2014
(In thousands)	Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents		Short-Term Marketable Securities		Long-Term Marketable Securities
Cash	$	86,058	$	—	$	—		$	86,058	$	86,058	$	—	$	—
Available-for-sale:
Level 1:
Money market funds	2,575,403		—		—			2,575,403		2,575,403		—		—
U.S. treasury securities	1,641,228		1,762		(8,059		)	1,634,931		18,624		45,038		1,571,269
Subtotal	4,216,631		1,762		(8,059		)	4,210,334		2,594,027		45,038		1,571,269
Level 2:
U.S. agency securities	27,379		23		(5		)	27,397		—		11,215		16,182
Non-U.S. government securities	18,610		5		(2		)	18,613		—		17,080		1,533
Municipal bonds	2,000		1		(2		)	1,999		—		—		1,999
Corporate debt securities	214,217		448		(92		)	214,573		—		60,726		153,847
Subtotal	262,206		477		(101		)	262,582		—		89,021		173,561
Total	$	4,564,895	$	2,239	$	(8,160	)	$	4,558,974	$	2,680,085	$	134,059	$	1,744,830

	December 31, 2013
(In thousands)	Cost		Unrealized Gains		Unrealized Losses			Fair Value		Cash and Cash Equivalents		Short-Term Marketable Securities		Long-Term Marketable Securities
Cash	$	71,880	$	—	$	—		$	71,880	$	71,880	$	—	$	—
Available-for-sale:
Level 1:
Money market funds	2,763,094		—		—			2,763,094		2,763,094		—		—
U.S. treasury securities	1,604,450		15		(28,298		)	1,576,167		34,184		39,262		1,502,721
Subtotal	4,367,544		15		(28,298		)	4,339,261		2,797,278		39,262		1,502,721
Level 2:
U.S. agency securities	53,755		33		(18		)	53,770		—		26,999		26,771
Non-U.S. government securities	18,352		5		—			18,357		—		9,306		9,051
Municipal bonds	2,603		—		(7		)	2,596		—		603		1,993
Corporate debt securities	219,491		425		(69		)	219,847		—		65,317		154,530
Subtotal	294,201		463		(94		)	294,570		—		102,225		192,345
Total	$	4,733,625	$	478	$	(28,392	)	$	4,705,711	$	2,869,158	$	141,487	$	1,695,066

Schedule of Investments Classified by Contractual Maturity Date (Table Text Block)

The adjusted cost and estimated fair value of marketable debt securities (corporate debt securities, municipal bonds, U.S. and foreign government securities, and U.S. treasury securities) as of September 26, 2014, 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 26, 2014
(In thousands)	Cost		Estimated Fair Value
Due in one year or less	$	152,554	$	152,683
Due after one year through five years	1,351,050		1,343,299
Due between six and ten years	399,830		401,531
	$	1,903,434	$	1,897,513