Balance Sheet Details - Other Non-Current Assets (Detail) (USD $) In Millions, unless otherwise specified	Jan. 24, 2014	Apr. 26, 2013
Auction rate securities	$ 40.4	$ 42.0
Deferred tax assets	224.3	200.4
Other assets	253.7	242.2
Other non-current assets	$ 518.4	$ 484.6

Total of debt securities categorized neither as held-to-maturity nor trading which are intended be sold or mature more than one year from the balance sheet date or operating cycle, if longer.

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Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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