This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 10

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-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (c)-(e)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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This item represents the cost of cash equivalents and debt and equity securities, 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 debt securities at fair value maturing in the next rolling twelve months following the latest balance sheet presented.

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Amount of debt securities at fair value maturing in the second rolling twelve months through the fifth rolling twelve months following the latest balance sheet presented.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents cash equivalents and short-term investments as of the balance sheet date.

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Bonds or similar securities.

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Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 29, 2013	Jun. 29, 2013	Jun. 28, 2014	Dec. 31, 2013
Cash Equivalents and Investments [Line Items]
Amortized Cost			$ 1,536,975	$ 1,399,712
Unrealized Gain			988	371
Unrealized Loss			(124)	(243)
Fair Value			1,537,839	1,399,840
Debt securities due in one year or less			863,584	1,011,459
Debt securities due after one year through two years			606,741	314,184
Total debt securities			1,470,325	1,325,643
Loss on investments	(1,575)	(1,575)
Cash Equivalents [Member]
Cash Equivalents and Investments [Line Items]
Amortized Cost			48,970	36,966
Fair Value			48,970	36,966
Investments [Member]
Cash Equivalents and Investments [Line Items]
Amortized Cost			1,488,005	1,362,746
Unrealized Gain			988	371
Unrealized Loss			(124)	(243)
Fair Value			1,488,869	1,362,874
US Treasury Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost			547,265	556,438
Unrealized Gain			418	111
Unrealized Loss			(15)	(10)
Fair Value			547,668	556,539
Foreign Government Debt Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost			49,991	139,670
Fair Value			49,991	139,670
Corporate Debt Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost			872,275	629,477
Unrealized Gain			500	190
Unrealized Loss			(109)	(233)
Fair Value			872,666	629,434
Time Deposits
Cash Equivalents and Investments [Line Items]
Amortized Cost			67,367	74,050
Fair Value			67,367	74,050
Equity Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost			77	77
Unrealized Gain			70	70
Fair Value			$ 147	$ 147