Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Apr. 30, 2015	Jan. 31, 2015
Allowance for doubtful accounts receivable, current	$ 3,585	$ 4,217
Property, plant, and equipment, accumulated depreciation	340,341	334,619
Intangible assets, accumulated amortization	$ 213,919	$ 209,931
Common stock, no par value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, shares authorized	300,000us-gaap_CommonStockSharesAuthorized	300,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	116,181us-gaap_CommonStockSharesIssued	115,790us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	116,181us-gaap_CommonStockSharesOutstanding	115,790us-gaap_CommonStockSharesOutstanding

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount per share of no-par value common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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