Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 28, 2014	Dec. 29, 2013
Current assets
Accounts receivable, allowance for doubtful accounts	$ 15,900	$ 19,000
Shareholders' equity
Preference stock, par value (in dollars per share)	$ 2.50	$ 2.50
Preference stock, authorized shares (in shares)	5,000,000us-gaap_PreferredStockSharesAuthorized	5,000,000us-gaap_PreferredStockSharesAuthorized
Preference stock, shares issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, par value (in dollars per share)	$ 0.50	$ 0.50
Common stock, authorized shares (in shares)	600,000,000us-gaap_CommonStockSharesAuthorized	600,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued (in shares)	209,694,630us-gaap_CommonStockSharesIssued	209,694,630us-gaap_CommonStockSharesIssued
Treasury stock, at cost, shares (in shares)	85,168,478us-gaap_TreasuryStockShares	78,640,228us-gaap_TreasuryStockShares

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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