Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Apr. 30, 2013	Jan. 31, 2013
Allowance for doubtful accounts receivable, current	$ 4,752	$ 5,331
Property, plant, and equipment, accumulated depreciation	305,768	300,914
Intangible assets, accumulated amortization	$ 188,794	$ 186,060
Common stock, no par value	$ 0	$ 0
Common stock, shares authorized	300,000	300,000
Common stock, shares issued	112,599	112,902
Common Stock, shares outstanding	112,599	112,902