Investments and Fair Value Measurements-AFS FV and Unrealized Losses (Details 5) (USD $)	12 Months Ended
Dec. 28, 2014
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	$ 1,579,644,000
Less than 12 months, Gross Unrealized Loss	(4,691,000)
Greater than 12 months, Fair Value	16,465,000
Greater than 12 months, Gross Unrealized Loss	(49,000)
U.S. Treasury securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	25,162,000
Less than 12 months, Gross Unrealized Loss	(32,000)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
U.S. Government-sponsored agency securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	7,394,000
Less than 12 months, Gross Unrealized Loss	(18,000)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
International Government Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	81,719,000
Less than 12 months, Gross Unrealized Loss	(314,000)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Corporate notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	586,903,000
Less than 12 months, Gross Unrealized Loss	(2,046,000)
Greater than 12 months, Fair Value	2,494,000
Greater than 12 months, Gross Unrealized Loss	(6,000)
Asset-backed securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	137,007,000
Less than 12 months, Gross Unrealized Loss	(353,000)
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	0
Mortgage-backed Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	31,954,000
Less than 12 months, Gross Unrealized Loss	(132,000)
Greater than 12 months, Fair Value	9,518,000
Greater than 12 months, Gross Unrealized Loss	(41,000)
Municipal notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	709,505,000
Less than 12 months, Gross Unrealized Loss	(1,796,000)
Greater than 12 months, Fair Value	4,453,000
Greater than 12 months, Gross Unrealized Loss	$ (2,000)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

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

-Publisher FASB

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-Topic 320

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