CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parentheticals) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 25, 2015	Jan. 26, 2014	Jan. 27, 2013
Tax effect on net change in unrealized gains/losses on available-for-sale securities	$ (747)	$ 134	$ (126)
Tax effect on reclassification adjustments for net realized gains on available-for-sale securities	$ 51	$ 834	$ 178

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (d)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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