Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 27, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	$ 4,491,783	$ 4,510,571
Unrealized Gains	24,641	13,099
Unrealized Losses	(664)	(3,441)
Investments, Fair Value Disclosure	4,515,760us-gaap_InvestmentsFairValueDisclosure	4,520,229us-gaap_InvestmentsFairValueDisclosure
Cash and Cash Equivalents, Fair Value Disclosure	2,207,101	2,426,367
Short-Term Marketable Securities	168,849us-gaap_ShortTermInvestments	151,519us-gaap_ShortTermInvestments
Long-Term Marketable Securities	2,139,810us-gaap_LongTermInvestments	1,942,343us-gaap_LongTermInvestments
Cash [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash	67,652	57,505
Unrealized Gains	0	0
Unrealized Losses	0	0
Short-Term Marketable Securities	0	0
Long-Term Marketable Securities	0	0
Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	3,219,531	3,704,961
Unrealized Gains	20,551	12,721
Unrealized Losses	(101)	(2,302)
Investments, Fair Value Disclosure	3,239,981	3,715,380
Cash and Cash Equivalents, Fair Value Disclosure	2,139,449	2,367,299
Short-Term Marketable Securities	44,690	38,938
Long-Term Marketable Securities	1,055,842	1,309,143
Level 1 [Member] \| Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	2,133,747	2,366,799
Unrealized Gains	0	0
Unrealized Losses	0	0
Investments, Fair Value Disclosure	2,133,747	2,366,799
Cash and Cash Equivalents, Fair Value Disclosure	2,133,747	2,366,799
Short-Term Marketable Securities	0	0
Long-Term Marketable Securities	0	0
Level 1 [Member] \| US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	1,085,784	1,338,162
Unrealized Gains	20,551	12,721
Unrealized Losses	(101)	(2,302)
Investments, Fair Value Disclosure	1,106,234	1,348,581
Cash and Cash Equivalents, Fair Value Disclosure	5,702	500
Short-Term Marketable Securities	44,690	38,938
Long-Term Marketable Securities	1,055,842	1,309,143
Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	1,204,600	748,105
Unrealized Gains	4,090	378
Unrealized Losses	(563)	(1,139)
Investments, Fair Value Disclosure	1,208,127	747,344
Cash and Cash Equivalents, Fair Value Disclosure	0	1,563
Short-Term Marketable Securities	124,159	112,581
Long-Term Marketable Securities	1,083,968	633,200
Level 2 [Member] \| Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	22,236	21,186
Unrealized Gains	19	12
Unrealized Losses	0	(7)
Investments, Fair Value Disclosure	22,255	21,191
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Short-Term Marketable Securities	9,795	11,748
Long-Term Marketable Securities	12,460	9,443
Level 2 [Member] \| Foreign Government Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	41,819	31,281
Unrealized Gains	29	2
Unrealized Losses	(15)	(17)
Investments, Fair Value Disclosure	41,833	31,266
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Short-Term Marketable Securities	11,926	19,459
Long-Term Marketable Securities	29,907	11,807
Level 2 [Member] \| Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	2,000	2,000
Unrealized Gains	3	2
Unrealized Losses	0	0
Investments, Fair Value Disclosure	2,003	2,002
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Short-Term Marketable Securities	2,003	1,001
Long-Term Marketable Securities	0	1,001
Level 2 [Member] \| Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash and Available for Sale Securities, Cost	1,138,545	693,638
Unrealized Gains	4,039	362
Unrealized Losses	(548)	(1,115)
Investments, Fair Value Disclosure	1,142,036	692,885
Cash and Cash Equivalents, Fair Value Disclosure	0	1,563
Short-Term Marketable Securities	100,435	80,373
Long-Term Marketable Securities	$ 1,041,601	$ 610,949

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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