CONSOLIDATED BALANCE SHEET (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Jan. 24, 2015	Apr. 26, 2014
Current assets
Receivables, allowance	$ 10,336	$ 12,368
Shareholders' equity
Preferred shares, authorized (in shares)	5,000us-gaap_PreferredStockSharesAuthorized	5,000us-gaap_PreferredStockSharesAuthorized
Preferred shares, issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common shares, par value (in dollars per share)	$ 1	$ 1
Common shares, authorized (in shares)	150,000us-gaap_CommonStockSharesAuthorized	150,000us-gaap_CommonStockSharesAuthorized
Common shares, outstanding (in shares)	51,266us-gaap_CommonStockSharesOutstanding	51,981us-gaap_CommonStockSharesOutstanding

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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