Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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-Glossary Available-for-Sale Securities

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+ Details

- Definition

This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled maturities within one year of the balance sheet date or the normal operating cycle, whichever is longer; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 5

-Chapter 3

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-Name Accounting Research Bulletin (ARB)

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+ Details

- Definition

This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled maturities more than one year from the balance sheet date or operating cycle, if longer; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References+ Details

Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 30, 2012	Sep. 23, 2012	Jun. 24, 2012	Mar. 25, 2012	Dec. 25, 2011
Investment [Line Items]
Total long-term marketable securities	$ 170,990	$ 190,841	$ 4,444	$ 0	$ 0	$ 0	$ 0
Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	388,370		134,820
Long-term marketable securities	166,660		0
Marketable equity security [Member]
Investment [Line Items]
Available-for-sale security	4,330		4,444
U.S. Treasury securities [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	172,988		124,831
Corporate debt securities [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	76,840		0
Long-term marketable securities	100,140		0
U.S. agency securities [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	57,302		0
Long-term marketable securities	53,497		0
Municipal securities [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	30,650		0
Long-term marketable securities	13,023		0
Certificates of deposit [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	27,067		0
Commercial paper [Member] \| Marketable debt securities [Member]
Investment [Line Items]
Short-term marketable securities	$ 23,523		$ 9,989