CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 25, 2015	Jan. 26, 2014	Jan. 27, 2013
Net income	$ 630,587us-gaap_NetIncomeLoss	$ 439,990us-gaap_NetIncomeLoss	$ 562,536us-gaap_NetIncomeLoss
Net change in unrealized gains (losses) on available-for-sale securities, net of tax	3,061	(3,555)	(303)
Reclassification adjustments for net realized gains on available-for-sale securities included in net income, net of taxes	(94)	(1,549)	(330)
Other comprehensive income (loss)	2,967	(5,104)	(633)
Total comprehensive income	$ 633,554us-gaap_ComprehensiveIncomeNetOfTax	$ 434,886us-gaap_ComprehensiveIncomeNetOfTax	$ 561,903us-gaap_ComprehensiveIncomeNetOfTax

The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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