Investments and Fair Value Measurements-AFS FV and Unrealized Losses (Details 5)	Apr. 03, 2016 USD ($)
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	$ 330,286,000
Less than 12 months, Gross Unrealized Loss	(119,000)
Greater than 12 months, Fair Value	3,646,000
Greater than 12 months, Gross Unrealized Loss	(5,000)
International Government Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	1,654,000
Less than 12 months, Gross Unrealized Loss	(3,000)
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	117,285,000
Less than 12 months, Gross Unrealized Loss	(105,000)
Greater than 12 months, Fair Value	973,000
Greater than 12 months, Gross Unrealized Loss	(1,000)
Asset-backed securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	21,820,000
Less than 12 months, Gross Unrealized Loss	(11,000)
Greater than 12 months, Fair Value	2,535,000
Greater than 12 months, Gross Unrealized Loss	(3,000)
Mortgage-backed Securities [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	502,000
Less than 12 months, Gross Unrealized Loss	0
Greater than 12 months, Fair Value	138,000
Greater than 12 months, Gross Unrealized Loss	(1,000)
Municipal notes and bonds [Member]
Available-for-sale securities that were in an unrealized gain position
Less than 12 months, Fair Value	189,025,000
Less than 12 months, Gross Unrealized Loss	0
Greater than 12 months, Fair Value	0
Greater than 12 months, Gross Unrealized Loss	$ 0

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous 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

Reference 2: 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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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

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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
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 320
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-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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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)(1)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

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